Liquid feed nozzle, wet treatment, apparatus and wet treatment method

ABSTRACT

The wet treatment liquid feed nozzle of the invention comprises an introducing path  10  having an introducing port  7,  a discharging path  12  having a discharging port  15,  a crossing section  14  formed by causing the introducing path  10  and the discharging path  12  to cross at the other ends thereof, a nozzle assembly  50  having an opening section  6  opening to an object to be treated  1,  provided at the crossing section  14,  and pressure control means  13,  for controlling the difference between the pressure of the wet treatment liquid in contact with the object to be treated  1  and the atmospheric pressure provided at least on the discharging path  12  side so that the wet treatment liquid having been in contact with the object to be treated  1  via the opening section  6  does not flow to outside the discharging path  12.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a fluid saving type fluid feed nozzle,a fluid saving type treatment fluid feed nozzle apparatus, a washingtreatment system, and a treatment apparatus used for a wet treatment ora dry treatment such as washing, etching, development or stripping.

2. Description of the Related Art

From the point of view of washing from among the surface fluidtreatments of large-sized substrates such as a substrate for solar cell,a substrate for liquid crystal, a substrate for plastic package and thelike, the conventional art and problems will be described below.

A washing apparatus shown in FIG. 52 has conventionally been commonlyused. FIG. 52A is a side view, and FIG. 52B is a plan view.

Washing is carried out by feeding a washing liquid such as extra-purewater, electrolytic in water, ozone water or hydrogen water by means ofa wet treatment liquid feed nozzle 2 onto the upper surface of asubstrate 1 while moving the substrate 1, for example, in the arrow Adirection.

A washing liquid feed chamber 4, an opening section 6 guiding thewashing liquid onto the substrate and a washing liquid introducing port7 for introducing the washing liquid into the washing liquid feedchamber 4 are formed, as shown in FIG. 53 in this wet treatment liquidfeed nozzle 2.

An ultrasonic element 16 is provided above the washing liquid feedchamber 4 to improve washing effect by imparting an ultrasonic wave ofthe order of MHz band to the washing liquid.

A washing liquid such as extra-pure water, electrolytic ion water, ozonewater or hydrogen water is introduced from a washing liquid introducingport 7 into the washing liquid feed chamber 4 and fed to the substratesurface which is an object to be washed through the opening section 6 towash the same. After washing with the washing liquid, rinsing isperformed with a rinsing liquid (extra-pure water in general) by meansof a nozzle having a structure similar to that of the wet treatmentliquid feed nozzle 2 shown in FIG. 53 with a view to removing thewashing liquid from the surface of the object to be washed, and toeliminating residual particles and the like.

However, the aforesaid conventional art has the following problems.

(1) First, it requires a large consumption of a washing liquid or arinsing liquid.

For example, in order to achieve a cleanliness as represented by aamount of residual particles (for example, Al₂O₃ particles) remaining onthe substrate 1 on a level of 0.5 particles/cm², when a 500 mm squaresubstrate 1 is washed with a washing liquid such as electrolytic ionwater, and then rinsed with a rinsing liquid, the washing liquid and therinsing liquid must be fed at a flow rate within a range of from about25 to 30 L/min. The flow rate within a range of from 25 to 30 L/min isselected to permit imparting a stable ultrasonic wave. With a rate ofunder 25 to 30 L/min, therefore, it becomes impossible to stably impartan ultrasonic wave, and hence to wash cleanly. The consumption of thewashing liquid must currently be large for the reason as describedabove. A liquid consumption of 25 to 30 L/min is still required becausethe frequency of the ultrasonic wave is raised and the nozzle slit widthof ultrasonic washing is reduced. Here is a limit of the existing art.

(2) The second problem is that applicability of ultrasonic wave near theMHz band is limited. There is currently available ultrasonic wave withina range of from 0.7 to 1.5 MHz. In all cases of wet treatment,occurrence of a damage to the object to be treated should be avoided.For this purpose, it is the usual practice to use ultrasonic wave nearthe MHz band which does not cause a damage resulting from cavitation inwashing. A lower limit of usage is adopted from the point of view ofavoiding occurrence of a damage to the object to be treated. An upperlimit is selected in view of the fact that an effective power availablefor washing cannot be derived with ultrasonic wave of a frequency ofover 2 MHz. Conceivable reasons of impossibility to derive an effectivepower applicable for washing include the facts that the effective poweris low because of a problem in circuit of the ultrasonic element andthat, as shown in FIG. 53, the ultrasonic element is distant from theobject to be wet-treated, resulting in a large attenuation of ultrasonicpower.

(3) The third problem is that, because the washing liquid imparted withan ultrasonic wave as in the washing liquid feed chamber 4 is fed viathe narrow opening section 6 onto the object to be washed, there occursa considerable damping of ultrasonic output, this leading to thenecessity to increase the input power beyond necessity and therefore toa shorter service life of the ultrasonic oscillator. With an ultrasonicwave having a frequency within a range of from 0.7 to 1.5 MHz, while itis possible to derive an effective power applicable for washing, theultrasonic element is distant from the object to be washed as shown inFIG. 53, and damping of the ultrasonic power is still serious. Load onthe adhering surface of the ultrasonic oscillator is very large so thatonly a slight change in the feed amount of washing liquid or the likemay often cause a failure.

(4) The fourth problem lies in cleanliness after washing. Even when alarge amount of washing liquid (25 to 30 L/min) is used and a sufficientrinsing is carried out after washing as described above, the resultantcleanliness is limited to a level, resulting in an average cleanlinessof about 0.5 particles/cm².

When a higher cleanliness (about 0.05 particles/cm²) is demanded, theconventional washing technology cannot cope with this demand. Evenwithin a substrate, furthermore, there are fluctuations of cleanliness,and therefore, the portion on the side (b) opposite to the travel of thesubstrate 1 as shown in FIG. 52 shows a cleanliness lower than that ofthe portion (a) on the travelling side. As is clear from thedistribution of cleanliness shown in FIG. 52B, a problem is that theportion closer to the leading end (a) in the travelling direction has ahigher cleanliness, and cleanliness worsens toward the rear end (b) inthe travelling direction.

This is attributable to the fact that particles once removed adhereagain to the substrate surface while the washing liquid fed from thefeed nozzle to the substrate surface flows in the form of a liquid filmon the surface of the large-sized substrate to the substrate edge.

The present inventors obtained the following findings regarding washing,a form of wet treatment. Consideration on reasons why a high cleanlinesscould not be obtained from washing by means of a conventional washingapparatus as shown in FIG. 50 led to a conclusion that it was caused bythe following reasons. When the washing liquid is fed from the nozzleopening section 6, the leading end side (a) of the substrate 1 iswashed. However, since the substrate 1 travels in the arrow A direction,the washing liquid having washed the surface is transferred smoothlyalong the surface of the substrate 1 to the rear end (b) of thesubstrate 1. Because the washing liquid after washing containsparticles, these particles adhere again to the surface of the substrate1 during travel toward the (b) end side. The amount of accumulatedparticles is larger in the washing liquid after washing at a positioncloser to the rear end so that the amount of adhesion is larger, leadingto a poorer cleanliness.

The present inventors thus clarified that the cause of a poorercleanliness and an increased consumption of rinsing liquid lay inre-adhesion of once removed particles.

The present invention is therefore to prevent, in a wet treatment methodfor gradually feeding a wet treatment liquid to an object to bewet-treated, re-adhesion of a wet treatment liquid fed from the wettreatment liquid feed nozzle to the object to be wet-treated, byremoving the same from the object to be wet-treated without allowing itto come substantially into contact with portions other than the portionto which the wet treatment liquid has been fed. More particularly,re-adhesion is prevented by immediately removing the wet treatmentliquid having contributed to a wet treatment to outside the system.

The present inventors developed a wet treatment liquid feed nozzle, awet treatment apparatus and a wet treatment method as described above asa technique for preventing re-adhesion.

The invention has therefore an object to provide a liquid-saving typetreatment liquid feed nozzle, a treatment liquid feed nozzle apparatus,a washing system and a treatment apparatus which solve the problems ofthe conventional wet and dry treatment apparatuses and wet and drytreatment methods, permit reduction of the consumption of the treatmentliquid to under a tenth the conventional consumption, and allow toobtain a higher cleanliness than the conventional one.

Another object of the invention is to provide a treatment liquid feednozzle, a treatment liquid feed nozzle apparatus and a treatmentapparatus in which leakage of the treatment liquid from the treatedsurface of the object to be treated to outside is non-existent or veryslight, if any.

SUMMARY OF THE INVENTION

To solve the foregoing problems, the wet treatment liquid feed nozzle ofthe invention comprises a nozzle assembly which has an introducing pathhaving an introducing port for introducing a wet treatment liquid at anend thereof, a discharging path having a discharging port fordischarging the wet treatment liquid after a wet treatment to outsidethe wet treatment system and an opening section opening to an object tobe wet-treated provided at a crossing section formed by causing theintroducing path and the discharging path to cross at the other endsthereof; and pressure control means for controlling a difference betweenpressure of the wet treatment liquid in contact with the object to bewet-treated and the atmospheric pressure so as to prevent the wettreatment liquid in contact with the object to be wet-treated via theopening section after the wet treatment from flowing to outside thedischarging path.

By using this configuration, the treatment liquid comes into contactonly with the object to be treated and is therefore effectivelyutilized. Further, because the treatment liquid after use is immediatelyremoved to outside the system, inconveniences in the treated objectcaused by the treatment liquid after use can be eliminated.

The wet treatment liquid feed nozzle of the invention may be providedwith means for imparting an ultrasonic wave to the wet treatment liquid.

According to this nozzle, it is possible to impart an ultrasonicoscillation via the wet treatment liquid appropriately to the object tobe wet-treated, leading, for example in washing, to a remarkableimproving effect of cleanliness.

The wet treatment apparatus of the invention comprises at least:

a wet treatment liquid feed nozzle comprising a nozzle assembly whichhas an introducing path having an introducing port for introducing a wettreatment liquid at an end thereof, a discharging path having adischarging port for discharging the wet treatment liquid after a wettreatment to outside the wet treatment system and an opening sectionopening to an object to be wet-treated provided at a crossing sectionformed by causing the introducing path and the discharging path to crossat the other ends thereof; and pressure control means for controlling adifference between pressure of the wet treatment liquid in contact withthe object to be wet-treated and the atmospheric pressure so as toprevent the wet treatment liquid in contact with the object to bewet-treated via the opening section after the wet treatment from flowingto outside the discharging path;

means for causing a relative displacement of the wet treatment liquidfeed nozzle and the object to be wet-treated;

a wet treatment liquid feed source; and

means for feeding a wet treatment liquid from the wet treatment liquidfeed source to the introducing port of the wet treatment liquid feednozzle.

According to the wet treatment apparatus of the invention, it ispossible to optimize the relative position of the wet treatment liquidfeed nozzle and the object to be wet-treated, and hence to accomplish awet treatment while easily preventing leakage of the wet treatmentliquid and moving throughout the entire surface of the object to bewet-treated.

When moving the wet treatment liquid feed nozzle relatively to theobject to be wet-treated, in a structure in which the nozzle assemblyand the pressure controller are integrally formed, it suffices to movethe integral wet treatment liquid feed nozzle, and in a structure inwhich a part of the pressure controller is composed, for example, of alarge-sized pump, it is not necessary to move the pressure controller,but it suffices to move only the nozzle assembly.

The wet treatment method of the invention comprises the steps of:

gradually feeding a set treatment liquid from a wet treatment liquidfeed nozzle to an object to be wet-treated while causing a relativedisplacement of the object to be wet-treated and the wet treatmentliquid feed nozzle, and discharging the wet treatment liquid fed fromthe wet treatment liquid feed nozzle to the object to be wet-treatedwithout causing the wet treatment liquid to be in contact with portionsother than the portion to which the wet treatment liquid has been fed,by controlling a difference between the pressure of the wet treatmentliquid in contact with the object to be wet-treated and the atmosphericpressure.

According to the wet treatment liquid feed nozzle of the invention, itis possible to apply wet treatment to the entire surface of even anobject to be wet-treated larger in size than the wet treatment liquidfeed nozzle by causing a relative displacement of the object to bewet-treated and the wet treatment liquid feed nozzle.

The wet treatment liquid feed nozzle of the invention may be providedwith means for imparting an ultrasonic wave to the wet treatment liquid.

According to the wet treatment liquid feed nozzle of the invention, itis possible to effectively apply a wet treatment to an object to bewet-treated by imparting an ultrasonic wave via the wet treatment liquidto the object to be treated.

In the wet treatment liquid feed nozzle of the invention, a portion of aceiling opposite to the treatment surface of the object to bewet-treated should preferably be formed into a waved shape having aplurality of steps, and a plurality of ultrasonic elements shouldpreferably be provided at an angle to the treatment surface of theobject to be wet-treated on the stepped portion.

By using this structure, the gap between the ultrasonic elements and theobject to be treated becomes substantially uniform, and it is possibleto cause the ultrasonic vibration to act uniformly on the object to betreated.

In the wet treatment liquid feed nozzle of the invention, twointroducing paths may be formed to the right and the left of thecrossing section, with the discharging path in between.

By using this nozzle, the wet treatment liquid is fed in oppositedirections from the right and the left introducing paths, furtherreducing leakage of the treatment liquid.

In the wet treatment liquid feed nozzle of the invention, twodischarging paths may be formed to the right and the left of thecrossing section, with the introducing path in between.

By using this nozzle, the wet treatment liquid after use is dischargedthrough the right and the left discharging paths, thus reducing leakageof the treatment liquid.

The wet treatment liquid feed nozzle may be provided with a measuringsection capable of measuring the length of the distance to the wettreatment surface of the object to be wet-treated.

With this nozzle, it is possible to accurately determine the distance tothe object to be wet-treated, thus ensuring accurate control of the flowof the wet treatment liquid.

Further, another embodiment of the wet treatment liquid feed nozzle ofthe invention comprises an introducing path having at an end anintroducing port for introducing a wet treatment liquid, a dischargingpath having at an end a discharging port for discharging the wettreatment liquid after a wet treatment to outside the wet treatmentsystem, a crossing section formed by causing the introducing path andthe discharging path to cross at the other ends, and an opening sectionopening in a mesh shape toward an object to be wet-treated, provided atthe crossing section.

According to this wet treatment liquid feed nozzle of the invention, inwhich the opening has a mesh shape, the wet treatment liquid isprevented from dropping by surface tension of the wet treatment liquideven when the wet treatment liquid feed nozzle is kept away from theobject to be wet-treated.

A further embodiment of the wet treatment liquid feed nozzle of theinvention comprises an introducing path having at an end an introducingport for introducing a wet treatment liquid, a discharging path havingat an end a discharging port for discharging the wet treatment liquidafter a wet treatment to outside the wet treatment system, a crossingsection formed by causing the introducing path and the discharging pathto cross at the other ends, an opening section opening in a mesh shapetoward an object to be wet-treated, provided at the crossing section,and cilia or a film provided around the opening section in parallel withthe normal of a treatment surface of the object to be wet-treated.

According to the nozzle of this configuration, leakage of the wettreatment liquid in contact with the treatment surface of the object tobe treated to outside the system can be prevented by the cilia or thefilm.

Another embodiment of the wet treatment liquid feed nozzle of theinvention comprises an introducing path having at an end an introducingport for introducing a wet treatment liquid, a discharging path havingat an end a discharging port for discharging the wet treatment liquidafter a wet treatment to outside the wet treatment system, a crossingsection formed by causing the introducing path and the discharging pathto cross at the other ends, an opening section opening in a mesh shapetoward an object to be wet-treated, provided at the crossing section,and at least an auxiliary path communicating with the crossing sectionbetween the discharging path and the object to be wet-treated on theside of the discharging path.

According to this wet treatment liquid feed nozzle of the invention,when the treatment liquid at the crossing section is in short, it ispossible to keep pressure balance between the pressure of the wettreatment liquid and the atmospheric pressure by injecting the treatmentliquid by the use of an auxiliary path communicating with the crossingsection at which the introducing path and the discharging path crosseach other.

Further, another embodiment of the wet treatment liquid feed nozzle ofthe invention comprises an introducing path having at an end anintroducing port for introducing a wet treatment liquid, a dischargingpath having at an end a discharging port for discharging the wettreatment liquid after a wet treatment to outside the wet treatmentsystem, a crossing section formed by causing the introducing path andthe discharging path to cross at the other ends, an opening sectionopening in a mesh shape toward an object to be wet-treated, provided atthe crossing section, and a parallel flow section permitting flow of thewet treatment liquid provided in parallel with the treatment surface ofthe object to be wet-treated.

According to this wet treatment liquid feed nozzle of the invention,there occurs no disturbance in the flow of the wet treatment liquidafter use and the wet treatment liquid introduced anew from theintroducing port, ensuring efficient replenishing.

Another embodiment of the wet treatment liquid feed nozzle of theinvention comprises an introducing path having at an end an introducingport for introducing a wet treatment liquid, a discharging path havingat an end a discharging port for discharging the wet treatment liquidafter a wet treatment to outside the wet treatment system, a crossingsection formed by causing the introducing path and the discharging pathto cross at the other ends, an opening section opening toward an objectto be wet-treated, provided at the crossing section, and an outersurface of the periphery of the opening section made parallel to thetreatment surface of the object to be wet-treated.

According to this wet treatment liquid feed nozzle of the invention,there is available a wide contact surface between the wet treatmentliquid and the object to be wet-treated, thus leading to a highertreatment efficiency.

Further, another embodiment of the wet treatment liquid feed nozzle ofthe invention comprises an introducing path having at an end anintroducing port for introducing a wet treatment liquid, a dischargingpath having at an end a discharging port for discharging the wettreatment liquid after a wet treatment to outside the wet treatmentsystem, a crossing section formed by causing the introducing path andthe discharging path to cross at the other ends, an opening sectionopening in a mesh shape toward an object to be wet-treated, provided atthe crossing section, and a sealing member for sealing the crossingsection from outside provided on a peripheral edge of the openingsection, in a state in contact with the object to be wet-treated or witha support for supporting the object to be wet-treated.

According to this wet treatment liquid feed nozzle of the invention, itis possible to seal the portion to be treated of the object to betreated from outside, thus permitting complete prevention of leakage ofthe liquid.

A wet treatment apparatus of the invention comprises at least a wettreatment liquid feed nozzle or a wet treatment liquid feed nozzleapparatus of any of the aforesaid embodiments; means for causing arelative displacement of the wet treatment liquid feed nozzle or the wettreatment liquid feed nozzle apparatus; a wet treatment liquid feedsource; and means for feeding from the wet treatment liquid feed sourceto the introducing port of the wet treatment liquid feed nozzle.

According to this wet treatment apparatus, it is possible toappropriately treat the entire surface to be treated of the object to betreated larger in size than the nozzle or the nozzle apparatus bycausing a relative displacement of the nozzle or the nozzle apparatus ofany of the aforesaid embodiments, to optimize the distance between thenozzle or the nozzle apparatus and the object to be treated, and toappropriately keep the wet treatment liquid.

A further embodiment of the fluid treatment apparatus of the inventioncomprises a fluid treating path for bringing fluid introduced from anopening and returning the treating fluid to the opening; an introducingpath for introducing the treating fluid to the fluid treating path; anda discharging path for discharging the treating fluid brought back fromthe fluid treating path into the opening.

According to the fluid treatment apparatus of the invention, theconsumption of the treating fluid can be reduced to under a tenth theconventional consumption of the same.

The scope of this treatment covers washing with a liquid, etching,polishing, electroless plating, coating, development and stripping ofresist of an object to be treated, patterning of a thin film, andanalysis of a surface deposit. In other words, the fluid treatmentapparatus of the invention is applicable for a washing apparatus, anetching apparatus, a polishing apparatus, an electroless platingapparatus, an apparatus for coating, developing and stripping of resist,a thin film patterning apparatus, and an analyzer.

To apply in a washing apparatus, an etching apparatus, a polishingapparatus, a plating apparatus, or a resist coating apparatus, itsuffices to feed a washing liquid, an etching liquid, a polishingliquid, a plating liquid, or a resist stripping liquid, respectively, toa fluid treating path as a treating fluid.

To use as a resist coating apparatus, it suffices to feed a fluid resistas a treating fluid to the fluid treating path, and in order to hardenthe resist, it suffices to irradiate a light onto the resist byproviding light irradiating means as described later (infrared-rayirradiating means, for example).

To achieve a developing apparatus, it suffices to provide, for example,laser irradiating means as light irradiating means, and to irradiate alaser onto the resist through a pattern mask.

A thin film patterning apparatus may be achieved by opening the resist,and then feed a CVD gas to the fluid treating path. For optical CVD, itsuffices to provide light irradiating means.

In the case of an analyzer, it suffices to feed a high-purity (forexample, an impurity concentration of a few ppt) inert gas to the fluidtreating path, incorporate substances to be measured on the object to betreated into the gas, and feed the incorporated gas from the dischargingpath into an external analyzer to analyze the kinds and the number ofelements to be measured.

When using for any of the aforesaid applications, it is convenient tobuild the fluid treatment apparatus as follows. After bringing atreating build introduced from the opening into contact with the objectto be treated, a fluid treating path for bringing the treating fluidback to the opening, an introducing path for introducing the treatingfluid to the fluid treating path, and a discharging path for dischargingthe treating fluid brought back from the fluid treating path into theopening are provided, and light irradiating means for irradiating alight onto the treating fluid is provided in the fluid treating path.

According to the fluid treatment apparatus of the invention, it ispossible to reduce the consumption of the treating fluid to under atenth the conventional consumption, and to improve the light irradiationefficiency.

When using the fluid treatment apparatus of the invention, in order tobring the treating liquid back to the opening after bringing thetreating fluid introduced from the opening into contact with the objectto be treated, it suffices to appropriately adjust the diameter of theopening, the distance between the object to be treated and the opening,and the pressure of the treating fluid, and to previously determinethese values for each fluid treatment apparatus.

For further simplification, it suffices to provide pressure controlmeans for bringing the treating fluid back to the opening of the fluidtreating path by controlling the difference between the pressure of thetreating fluid in contact with the object to be treated and theatmospheric pressure.

Any of a visible light and a non-visible light may be used as a light.For example, ultraviolet rays, infrared rays, or a laser beam (such asexcimer laser beam) are used appropriately in response to the purpose oftreatment of the object to be treated.

When the light irradiating means is detachably provided in the fluidtreating path, it is possible to impart general-purpose property becauseof the applicability as a washing apparatus provided with an ultrasonicelement having a high washing efficiency by detaching the lightirradiating means and attaching the ultrasonic element, thus providingan economic merit.

The washing treatment system of the invention comprises a gas treatingpath for bringing a treating gas introduced from an opening andreturning the treating as to the opening; an introducing path forintroducing the treating as to the gas treating path; a discharging pathfor discharging the treating gas brought back from the gas treating pathinto the opening; and light irradiating means for irradiating a lightonto the treating gas in the gas treating path; the gas treatingapparatus communicating with a washing treatment apparatus for washingthe object to be treated having been treated in the gas treatingapparatus.

As a washing treatment apparatus, it is desirable to use a washingtreatment apparatus comprising a washing treating path for bringing atreating liquid introduced from an opening and returning the treatingliquid to the opening; an introducing path for introducing the treatingliquid to the washing treating path; and a discharging path fordischarging the treating liquid brought back from the washing treatingpath into the opening.

It is needless to mention that this washing treatment apparatus shouldpreferably be provided with pressure control means bringing the washingliquid back to the opening of the washing treating path by controllingthe difference between the pressure of the washing liquid in contactwith the object to be treated and the atmospheric pressure.

Further, in the invention, the light is irradiated at a higherirradiating efficiency by irradiating the light by the light irradiatingmeans onto the treating fluid, thereby improving the ozone producingefficiency and the sterilizing rate in the treating fluid.

In the invention, the distance between the light irradiating means andthe object to be treated is far shorter than in the conventional art. Itis therefore possible to feed ozone to the object to be treated beforeexhaustion of the life of ozone, thus leading to an efficient treatmentof the object to be treated. In the fluid treatment apparatus of theinvention, the opening area of the opening may be variable.

For example, in a semiconductor wafer, the diameter of the object to betreated may vary. In this case, feeding the treatment fluid always in aconstant rate, in spite of the variation in diameter requiring a variedamount of treatment fluid from the opening to the object to be treatedwould be a waste of the treatment fluid. By making the opening areavariable in response to the diameter of the object to be treated,therefore, the amount of feed of the treatment fluid can be reduced fora smaller diameter, contributing to further reduction of the consumptionof the treatment fluid. In order to make the opening area variable, itsuffices to provide a movable cover onto the opening.

In the fluid treatment apparatus of the invention, a liquid sump shouldpreferably be provided around the opening.

When such a liquid sump is provided around the opening, the treatmentfluid after treatment is collected uniformly into the liquid sump fromthe portions surrounding the opening, not flowing through thedischarging path alone, and is discharged from the liquid sump. As aresult, the flow of the treatment fluid becomes uniform, permittinguniform treatment of the object to be treated.

Because the treatment fluid in the fluid treating path, which may leakto outside the fluid treatment apparatus, is once collected in theliquid sump, it is possible to prevent the fluid from leaking tooutside.

Provision of fine grooves causing capillary action in the liquid sump ismore effective for preventing leakage of the treatment liquid to outsidesince the treatment fluid collected in the liquid sump is sucked up inthe fine grooves by the capillary action.

Further, in the fluid treatment apparatus of the invention, the fluidtreating path and the discharging path should preferably communicatewith each other via the liquid sump.

When treating the object to be treated by means of the treatment fluid,bubbles may be produced in the treatment fluid. For example, thetreatment fluid reacts with the object to be treated or a substanceadhering to, or formed on, the surface thereof, generating a gas as areaction product.

As the treatment fluid has the discharging path as the only exit, thegenerated gas has no escape and remains contained in the treatmentfluid. The gas, if present in the treatment liquid, adheres to thesurface of the object to be treated and causes a delay in the progressof the essential reaction between the treatment fluid and the surface ofthe object to be treated, thus leading, for example, to a poorer washingefficiency of the object to be treated. This makes pressure control inthe fluid treating path difficult. Further, when imparting an ultrasonicwave to the treatment liquid still containing the gas in an amountexceeding the necessity, cavitation causes the ultrasonic wave to show aconsiderable damping, causing a decrease in the power serving to removeparticles, thus making it impossible to achieve a sufficient washingeffect.

In the invention, in contrast, there is provided a pressure adjustingport for positional adjustment of the gas-liquid interface communicatingwith the fluid treating path. By adjusting the pressure at the pressureadjusting port, therefore, it is possible to form a gas phase and aliquid phase in the fluid treating path. As a result, the gas producedby the treatment of the object to be treated is transferred from theliquid phase to the gas phase, and is as required discharged from thegas phase through the pressure adjusting port to outside. This permitscontrol of the amount of gas present in the treatment fluid, thus makingit possible to derive necessary and sufficient cavitation effect.

When imparting an ultrasonic wave, the gas-liquid interface between thegas and liquid phases forms an oscillation free interface, resulting ina more remarkable cavitation effect, thus assisting achievement of animproved washing effect.

By appropriately adjusting the pressure at the pressure adjusting port,it is possible to arbitrarily adjust the ratio of the gas phase to theliquid phase. By ensuring that the gas phase does not communicatedirectly with the discharging path, the gas does not flow into thedischarging path, but is discharged exclusively through the pressureadjusting port. The pressure adjusting port should preferably beprovided at the ceiling of the fluid treatment apparatus.

On the other hand, the treatment liquid after the treatment is collectedin the liquid sump provided around the opening, and is dischargedthrough the discharging path. When the liquid sum communicates with thedischarging path through capillary fine grooves, the treatment liquidcollected in the liquid sump after the treatment is sucked up into thedischarging path under the effect of capillary phenomenon, withoutdropping from the liquid sump.

In the invention, the treatment fluid is not limited to any particularlyform, but may be a gas a liquid, a gas-liquid mixture, any of varioussuspensions, or a paste.

According to the fluid treatment apparatus of the invention, theconsumption of the treatment fluid can be reduced to under a tenth theconventional consumption, thus permitting improvement of the lightirradiating efficiency.

According to the washing treatment system of the invention, theconsumption of the treatment fluid can be reduced to under a tenth theconventional one, thus permitting achievement of a higher degree oftreatment.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional side view of a wet treatment liquid feed nozzle ofan embodiment of the invention;

FIG. 2A is a bottom view of the embodiment shown in FIG. 1; and FIG. 2Bis a plan view of the embodiment shown in FIG. 1;

FIG. 3 is a conceptual view of a wet treatment liquid feed nozzle ofanother embodiment of the invention;

FIG. 4 is a sectional side view of a wet treatment liquid feed nozzle ofa further embodiment of the invention;

FIG. 5A is a bottom view of the embodiment shown in FIG. 4; and FIG. 5Bis a plan view of the embodiment shown in FIG. 4;

FIG. 6 is a plan view of a wet treatment liquid feed nozzle of a furtherembodiment of the invention;

FIG. 7 is a sectional side view of a wet treatment liquid feed nozzle ofa further embodiment of the invention;

FIG. 8A is a sectional side view, and FIG. 8B is a plan view of afurther embodiment of the invention;

FIG. 9A is a sectional side view, and FIG. 9B is a plan view,respectively, of a further embodiment of the invention;

FIG. 10A is a sectional side view, and FIG. 10B is a plan view,respectively, of a further embodiment of the invention;

FIG. 11A is a sectional side view, and FIG. 11B is a plan view,respectively, of a further embodiment of the invention;

FIG. 12A is a sectional side view and FIG. 12B is a plan view of a wettreatment apparatus of an embodiment of the invention;

FIGS. 13A, 13B and 13C are sectional plan views illustrating a washingapparatus of an embodiment of the invention;

FIGS. 14A, 14B and 14C are sectional side views illustrating the washingapparatus of the embodiment of the invention;

FIGS. 15A, 15B and 15C are sectional side views illustrating a washingapparatus of another embodiment of the invention;

FIG. 16 is a sectional view of a wet treatment apparatus of anembodiment of the invention;

FIG. 17 is a sectional view of a wet treatment apparatus of anotherembodiment of the invention;

FIG. 18A is a graph illustrating results of an example and a comparativeexample of rotary washing, and FIG. 18B, of transfer washing;

FIG. 19 is a sectional side view of a wet treatment liquid feed nozzleof an embodiment of the invention;

FIG. 20A is a bottom view of the embodiment shown in FIG. 19; and FIG.20B is a plan view of the embodiment shown in FIG. 19;

FIG. 21 is a sectional side view of a wet treatment liquid feed nozzleof another embodiment of the invention;

FIG. 22A is a bottom view of the embodiment shown in FIG. 21; and FIG.22B is a plan view of the embodiment shown in FIG. 21;

FIG. 23A is a sectional side view and FIG. 23B is a plan view,respectively, of a further embodiment of the invention;

FIG. 24A is a sectional side view and FIG. 24B is a plan view,respectively, of a further embodiment of the invention;

FIG. 25A is a sectional side view and FIG. 25B is a plan view,respectively, of a further embodiment of the invention;

FIG. 26 is a sectional side view of a wet treatment liquid feed nozzleof a further embodiment of the invention;

FIG. 27 is a sectional side view of a wet treatment liquid feed nozzleof a further embodiment of the invention;

FIG. 28A is a sectional side view and FIG. 28B is a plan view,respectively, of a further embodiment of the invention;

FIG. 29A is a sectional side view and FIG. 29B is a plan view in whichthe mesh 265 is omitted, respectively, of a further embodiment of theinvention;

FIG. 30A is a sectional side view and FIG. 30B is a plan view in whichthe mesh 265 is omitted, respectively, of a further embodiment of theinvention;

FIG. 31A is a sectional side view and FIG. 31B is a plan view,respectively, of a further embodiment of the invention;

FIG. 32 is a sectional side view of a wet treatment liquid feed nozzleof a further embodiment of the invention;

FIG. 33 illustrates sectional side view of a wet treatment liquid feednozzle of a further embodiment of the invention: FIG. 33A is an examplein which it is brought into contact with a support stand, and FIG. 33Bis an example in which it is brought into contact with an outer edge ofthe object to be wet-treated;

FIG. 34A is a sectional side view and FIG. 34B is a plan view,respectively, of a further embodiment of the invention;

FIG. 35 is a sectional view of a wet treatment liquid feed nozzle of anembodiment of the invention;

FIG. 36A is a bottom view of a wet treatment liquid feed nozzle of afurther embodiment of the invention as viewed from below; and FIG. 36Bis a plan view of the same as viewed from above;

FIG. 37 is a sectional side view of a wet treatment liquid feed nozzleapparatus of a further embodiment of the invention;

FIG. 38 is a sectional side view of a wet treatment liquid feed nozzleapparatus of another embodiment of the invention;

FIG. 39A is a graph illustrating results of an example of rotarywashing, and FIG. 39B, of transfer washing;

FIG. 40 is a sectional side view of a fluid treatment apparatus of anembodiment of the invention;

FIG. 41A is a bottom view of the embodiment shown in FIG. 40, and FIG.41B is a plan view of the embodiment shown in FIG. 40;

FIG. 42 is a conceptual view of a fluid treatment apparatus of anotherembodiment of the invention;

FIG. 43 is a sectional side view of a fluid treatment apparatus of afurther embodiment of the invention;

FIG. 44 is a plan view of a fluid treatment apparatus of a furtherembodiment of the invention;

FIG. 45 is a sectional side view of a washing treatment apparatus of afurther embodiment of the invention;

FIG. 46 is a sectional side view of a further embodiment of theinvention;

FIG. 47 is a sectional view illustrating a further embodiment of thefluid treatment apparatus;

FIG. 48 is a sectional view illustrating a further embodiment of thefluid treatment apparatus;

FIG. 49 is a sectional view illustrating a further embodiment of thefluid treatment apparatus;

FIG. 50A is a sectional side view of a washing treatment system of anembodiment of the invention; and FIG. 50B is a front view of the same;

FIG. 51 is a sectional side view of a washing treatment system ofanother embodiment of the invention;

FIG. 52A is a side view and FIG. 52B is a plan view, respectively, of awashing apparatus of a conventional case;

FIG. 53 is an enlarged view of a wet treatment liquid feed nozzle shownin FIG. 52;

DESCRIPTION OF THE PREFERRED EMBODIMENT

A first embodiment of the wet treatment liquid feed nozzle of thepresent invention is illustrated in FIGS. 1 and 2.

FIG. 1 is a sectional side view; FIG. 2A is a bottom view, and FIG. 2Bis a plan view.

In FIGS. 1, 2 is a wet treatment liquid feed nozzle. This wet treatmentliquid feed nozzle 2 comprises mainly a nozzle assembly 50 and apressure controller 13.

More particularly, the nozzle assembly 50 comprises an introducing path10 having an introducing port 7 for introducing a wet treatment liquid 5at an end thereof, a discharging path 12 having a discharging port 15for discharging the wet treatment liquid 5 after a wet treatment tooutside the wet treatment system and an opening section 6 opening to anobject to be wet-treated (substrate) 1 provided at a crossing section 14formed by causing the introducing path 10 and the discharging path 12 tocross at the other ends thereof. A pressure controller 13 is provided atleast on the side of the discharging path 12 so as to take balancebetween the pressure of the wet treatment liquid in contact with theopen air of the opening section 6 (including the surface tension of thewet treatment liquid and the surface tension of the treated surface ofthe object to be wet-treated) and the atmospheric pressure and so thatthe wet treatment liquid having been in contact with the object to bewet-treated 1 after a wet treatment.

In this embodiment, the pressure controller 13 comprises areduced-pressure pump provided on the discharging port 15 side. Bycontrolling the sucking pressure of the reduced-pressure pump, thepressure of the wet treatment liquid, and hence the difference betweenthe atmospheric pressure and the pressure of the wet treatment liquidare controlled.

More particularly, with the use of the reduced-pressure pump for thepressure controller 1 on the discharging path 12 side, the force ofsucking the wet treatment liquid of the crossing section 14 incontrolled by means of this reduced-pressure pump to take balancebetween the pressure of the wet treatment liquid in contact with theopen air at the opening section 6 (including the surface tension of thewet treatment liquid and the surface tension of the treated surface ofthe object to be wet treated) and the atmospheric pressure. That is, byassuming that the relationship between the pressure Pw of the wettreatment liquid in contact with the open air at the opening section 6(including the surface tension of the wet treatment liquid and thesurface tension of the treated surface of the object to be wet-treated)and the atmospheric pressure Pa is Pw≈Pa, the wet treatment liquid fedto the substrate 1 via the opening section 6 and in contact with thesubstrate 1 is discharged into the discharging path 12 without leakingto outside the wet treatment liquid feed nozzle.

The ceiling of the crossing section should preferably have a shapeproducing Coanda effect, which makes it easier to take balance ofpressure.

In other words, the wet treatment liquid 5′ fed from the wet treatmentliquid feed nozzle to the object to be wet-treated (substrate) 1 isremoved from the object to be treated (substrate) without being broughtinto contact with portions other than the portion to which the wettreatment liquid has been fed (opening section 6).

In this embodiment, as is known from FIG. 2, there introducing paths 10are provided in parallel with each other.

Three discharging paths 12 are also provided in parallel with each otherto correspond to the introducing paths 10. By providing a plurality ofintroducing paths and discharging paths in the longitudinal direction ofthe wet treatment liquid feed nozzle 2 (up-down direction in FIG. 2) asdescribed above, it is possible to achieve a uniform washing efficiencyin the longitudinal direction.

The surface of the wet treatment liquid feed nozzle 2 should preferablebe formed with stainless steel having an outermost passive filmcomprising chromium oxide alone, stainless steel provided with a mixedfilm of aluminum oxide and chromium oxide on the surface thereof, oragainst ozone water, titanium having an electrolytically polishedsurface, because of the absence of elution of impurities into thewashing liquid. A surface in contact with the liquid, made of quarts, issuitable for feeding of all wet treatment liquids except for fluoricacid.

The angle θ₁ between the introducing path 10 and the substrate 1 can beappropriately selected within a range of from 0 to 90°.

On the other hand, the angle θ₂ between the discharging path 12 and thesubstrate 1 can be selected appropriately within a range of from 0to90°.

The angle θ₁ between the introducing path 10 and the substrate 1 and theangle θ₂ between the discharging path 12 and the substrate 1 arearbitrarily set in view of the contact efficiency of the wet treatmentliquid with the substrate, the discharging efficiency of the treatedproduct, the shape of the crossing section, the shape of the openingsection, the area thereof and the like.

The distance H2 between the portion of the ceiling 18 of the crossingsection 14 facing the object to be wet-treated (substrate) 1 the closestthereto, on the one hand, and the opening section 6 closest to theobject to be wet-treated (substrate) 1, on the other hand, shouldpreferable be within a range of from 1 to 50 mm, or more preferably,from 2 to 20 mm. A distance H2 smaller than 1 mm makes it difficult forthe wet treatment liquid to flow, leading to poorer contact efficiencyof the wet treatment liquid with the substrate and dischargingefficiency of the treated substrate. A distance H2 of over this rangecauses presence of wet treatment liquid in a large quantity in the wettreatment liquid feed nozzle 2, leading to a heavier wet treatmentliquid feed nozzle 2, thus causing troubles in the displacement of thewet treatment liquid feed nozzle 2.

The distance H1 (distance between the object to be treated 1 and theopening section 6) should preferably be within a range of from 0.1 to 5mm, or more preferably, from 1 to 2 mm.

The value of H1 may sometimes vary because of vibration of the transfermachine or one uneven surface of the substrate. It is thereforedesirable to provide a sensor for measuring H1 and means for separatingor bringing nearer the wet treatment liquid feed nozzle 2 in response toa signal from the sensor relative to the object to be treated. At leasttwo such length measuring units should preferably be provided at twopositions with the nozzle assembly 50 in between in FIG. 2A. This iswith a view to ensuring accurate control of the flow of the wettreatment liquid while keeping a constant distance between the object tobe wet-treated 1 and the opening 6 for the entire wet treatment liquidfeed nozzle. The length measuring accuracy should preferable be smallerthan 0.1 mm. Because the lower limit of the distance between the wettreatment liquid feed nozzle and the object to be wet-treated shouldpreferably be 0.1 mm, and this distance should accurately be controlled.

In FIG. 1, 19 is a contact preventing gas ejecting section. The contactpreventing gas ejecting section is provided at least in any of theintroducing path 10 and the discharging path so that the opening section6 does not come into contact with the object to be wet-treated uponlifting up the object to be wet-treated, because of unbalance betweenthe pressure of the wet treatment liquid in contact with the open air atthe opening section and the atmospheric pressure. The gas used for thispurpose should preferably be nitrogen gas or an inert gas, or may be airfree from impurities (particularly water).

In this embodiment, balance between the pressure of the wet treatmentliquid in contact with the object to be wet-treated as shown in FIG. 3and the atmospheric pressure may be controlled by a simpler system.

The pressure controller 1 on the discharging path 12 side controls thesucking force of the wet treatment liquid at the crossing section 14caused by the weight of the wet treatment liquid itself based on thesyphon principle produced by the difference in height between theopening section 6 and an end of the discharging path 12 (the end open tothe open air), to take balance between the pressure of the wet treatmentliquid in contact with the open air at the opening section 6 (includingthe surface tension of the wet treatment liquid and the surface tensionof the treated surface of the object to be wet-treated) and theatmospheric pressure.

More specifically, a water discharging unit 27 is connected to thedischarging port 15 of the wet treatment liquid feed nozzle 2 via awater discharge piping 25, and the water discharging unit 27 is held bya holder 28. The holder 28 is attached to, for example, a streetslidably vertically in the drawing.

A value 30 is attached to the leading end of the water discharging unit27. The value 30 is opened and closed by a value drive 29.

On the other hand, the embodiment shown in FIG. 3 has a controller 22which drives a robot and the value drive 29 on the basis of a signalfrom the pressure sensor for detecting the pressure of the wet treatmentliquid in the introducing path 10. The robot is for moving up and downthe holder 28. When the value is open, the pressure of the wet treatmentliquid in contact with the object to be wet-treated can be controlledthrough vertical displacement of the water discharging unit 27.

A second embodiment of the wet treatment liquid feed nozzle of theinvention is illustrated in FIG. 4.

In FIG. 4, 2 is a wet treatment liquid feed nozzle. The wet treatmentliquid feed nozzle 2 has the following configuration.

The wet treatment liquid feed nozzle 2 comprises an introducing path 10having an introducing port 7 for introducing a wet treatment liquid 5 atan end thereof, a discharging path 12 having a discharging port 15 fordischarging the wet treatment liquid 5′ after a wet treatment to outsidethe wet treatment system and an opening section 6 opening to an objectto be wet-treated (substrate) provided at a crossing section 14 formedby causing the introducing path 10 and the discharging path 12 to crossat the other ends thereof, and an ultrasonic element 16 providedopposite to the object to be wet-treated, for imparting an ultrasonicwave during wet treatment of the object to be wet-treated. The wettreatment liquid feed nozzle has also an attachment guide 20 fordetachably attaching the ultrasonic element 16 and the ultrasonicelement 16 slides vertically in FIG. 4 along an attachment guide 20 topermit attachment and detachment. Further, there is provided, on thedischarging path 12 side, a pressure controller 13 so as to ensure flowof the wet treatment liquid having been in contact with the object to betreated after completion of the wet treatment through control of balancebetween the pressure of the wet treatment liquid in contact with theopen air at the opening section 6 (including the surface tension of theset treatment liquid and the surface tension of the treated surface ofthe object to be treated) and the atmospheric pressure. This pressurecontroller is the same as the pressure controller described previously.

FIG. 5A is a bottom view, and FIG. 5B is a plan view of the wettreatment liquid feed nozzle shown in FIG. 4.

The ultrasonic element 16 provides an output of ultrasonic wave having afrequency of at least 19 KHz. It should preferably be a megasonicultrasonic element having a frequency within a range of from 0.2 to 5MHz.

The angle θ₃ between the ultrasonic element 16 and the substrate 1 canbe appropriately selected within a range of from 0 to 90°, orpreferably, from 2 to 45°.

When a megasonic ultrasonic wave is imparted as described above, thereis available a remarkable improving effect of cleanliness.

FIG. 5 illustrates a case where a single ultrasonic element 16 isprovided; and FIG. 6 illustrates a case where a plurality of suchelements are provided. In the example shown in FIG. 6, three ultrasonicelements 16 a, 16 b and 16 c in the longitudinal direction (up-downdirection in FIG. 6). When a plurality of ultrasonic elements areprovided, it is possible to appropriately change the ultrasonicfrequency or output, thereby permitting uniform washing.

These elements may be arranged either in the longitudinal direction orin the transverse direction. A plurality of ultrasonic elements may bearranged both in the longitudinal and transverse directions.

As shown in FIG. 7, the second embodiment comprises means forcontrolling the difference between the pressure of the wet treatmentliquid and the atmospheric pressure, a reduced-pressure pump (a waterdischarge pump in this example) 17 provided in the downstream of thedischarging path 12, and a feed pump 33 provided in the upstream of theintroducing path 10. It may further comprise a pressure sensor 13 fordetecting the pressure of the wet treatment liquid in contact with theobject to be wet-treated, and a controller 32 for controlling drive ofthe reduced-pressure pump 17 and the feed pump 33 in accordance with asignal from the pressure sensor 31. Which the embodiment shown in FIG. 1is applicable when the pressure of the wet treatment liquid is constanton the introducing port 7 side, the present embodiment, in which thepressure of the wet treatment liquid on the introducing side isdetected, permits achievement of accurate pressure control, giving anexcellent cleanliness.

In a third embodiment of the wet treatment liquid feed nozzle of theinvention shown in FIG. 8, the portion of the ceiling opposite to thetreated surface of the object to be wet-treated has a plurality of steps40 a, 40 b, 40 c, 41 a,41 b and 41 c. In FIG. 8, the ceiling steps 40 a,40 b and 40 c inclining toward the right down are provided withultrasonic elements 16 a, 16 b and 16 c, respectively.

Since, in this embodiment, the ultrasonic elements 16 a, 16 b and 16 care provided on the right-down portions of the ceiling, it is possibleto impart an ultrasonic wave so as to be opposite to the wet treatmentliquid fed from the introducing path 10 to the crossing section 14.Because the ceiling has a stepped shape, the gaps formed between theultrasonic element and the object to be wet-treated are substantiallyuniform, thereby permitting uniform washing.

The elements 16 a, 16 b and 16 c may be composed of ultrasonic elementswith different frequencies.

In the embodiment shown in FIG. 8, a rectifying section 4 for achievinga uniform flow of the wet treatment liquid in each of the portions ofthe introducing path 10 and the discharging path 12 facing the crossingsection 14. The rectifying section 4 may be formed with a filter and aslit, for example.

FIG. 9 illustrates a fourth embodiment of the wet treatment liquid feednozzle of the invention.

In the fourth embodiment, a discharging path 12 is provided verticallyto the substrate 1, and introducing paths 10 a and 10 b aresymmetrically arranged with the discharging path 12 in between.

In this embodiment, the wet treatment liquid is fed from the right andleft introducing paths 10 a and 10 b to the opposed substrate 1. Thisleads to a further smaller leakage of washing liquid, and the washingliquid after washing is more rapidly carried away to the dischargingpath 12. Ultrasonic wave frequencies may be the same or different forthe two ultrasonic elements 16. The two ultrasonic elements mayoscillate in pulses alternately at certain time intervals orsimultaneously.

FIG. 10 illustrates a fifth embodiment of the wet treatment liquid feednozzle of the invention.

In the fifth embodiment, an introducing path 10 is provided verticallyto the substrate 1, and discharging paths 12 a and 12 b aresymmetrically arranged with the introducing path 10 in between.

In this wet treatment liquid feed nozzle, both the introducing path andthe discharging paths are vertically formed to the substrate.

Now, the first embodiment of the wet treatment apparatus of theinvention will be described below.

When a wet treatment apparatus is formed with the use of the wettreatment liquid feed nozzle 2 shown in FIGS. 1 and 2, the openingsection 6 of the wet treatment liquid feed nozzle 2 is arranged to facethe substrate 1 and it suffices to provide means for causing a relativedisplacement of the wet treatment liquid feed nozzle 2 and the substrate1, for example, a roller transfer machine (not shown) for transferringthe substrate 1.

There is also provided a wet treatment liquid source and means forfeeding the wet treatment liquid from the wet treatment liquid feednozzle. A heating unit, a temperature adjusting unit and a temperatureholding unit should preferably be provided at appropriate positions tocope with the necessity to treat an object to be treated at atemperature within a range of from 70 to 80° C. such as in a resiststripping step.

In FIG. 11, the wet treatment liquid feed nozzles 2 aF and 2 aB arearranged in pair with the object to be treated held in between tosimultaneously carry out a wet treatment of both the surface and theback of the object to be treated.

Three lines including wet treatment liquid feed nozzles (2 aF and 2 aB)for electrolytic ion water washing (an embodiment of wet treatment), wettreatment liquid feed nozzles (2 bF and 2 bB) for extra pure waterrinsing (wet treatment), and wet treatment liquid feed nozzles (2 cF and2 cB) for IPA (isopropyl alcohol) drying, sequentially in the travellingdirection of the object to be treated. The pressure controller is notshown in FIG. 11.

The pair of wet treatment liquid feed nozzles 2 aF and 2 aB are incontact with each other at the both end thereof to form a tunnel-likespace as shown in FIG. 11B, and the object to be wet-treated flowstherethrough. Therefore, even when the wet treatment liquid from theside of an end surface (s surface perpendicular to the sheet plane inthe drawing) of the object to be wet-treated, the wet treatment liquidthus flowing out can be received by the lower wet treatment liquid feednozzle 2 aB.

Because the washing efficiency is higher on the back (lower surface),the ultrasonic element is provided only on the surface (upper surface).When the same wet treatment liquid is employed, A single pressurecontroller may conduct pressure control.

FIG. 12A is a sectional side view, and FIG. 12B is a plan view, of acase where the object to be wet-treated is vertically moved.

FIG. 13 is a sectional plan view of the washing apparatus as viewed fromabove. FIGS. 13A, 13B and 13C represent a case where the object to betreated is place upright, and the wet treatment liquid feed nozzle islongitudinally provided at right angles to the travelling direction ofthe object to be treated 1. The object to be treated 1 is horizontallytransferred. In this case, the object to be wet-treated has no up-downrelationship and the washing efficiency is the same for the surface aswell as for the back. Ultrasonic elements 16 may be provided on the back(FIG. 13C), the surface (FIG. 13B) or the surface and the back (FIG.13A).

FIG. 14 is a sectional side view of the washing apparatus as viewed froma side. The object to be wet-treated is placed upright and lifted up.

In the case shown in FIG. 14, as in that shown in FIG. 13, the object tobe wet-treated has no up-down relationship, and the washing efficiencyis the same for the surface as well as for the back. Therefore, theultrasonic elements 16 may be provided on the back (FIG. 14C), thesurface (FIG. 14B), or the surface and the back (FIG. 14A).

FIG. 15 is a sectional side view of the washing apparatus as viewed froma side, with the back as the lower surface, and the surface as the uppersurface. In this case, therefore, the object to be wet-treated 1 isplaced horizontally, and transferred in the horizontal direction. Sincethe washing effect is high on the back an arrangement of the ultrasonicelements 16 shown in FIG. 15B is usually used.

Applicable wet treatment liquid include extra-pure water, electrolyticion water, ozone water, hydrogen water, and the like for the washingstep, and for the other wet treatment steps, and etching solution, adeveloping solution or stripping liquid is suitably used.

FIG. 16 illustrates a variant of the embodiment shown in FIG. 9 of thewet treatment liquid feed nozzle of the invention.

This variant has the same basic structure as that shown in FIG. 9:discharging paths 12 a and 12 b are provided, with two opposedintroducing paths 10 a and 10 b in between. A difference is that thedistance between the exits of the introducing paths 10 a and 10 b, onthe one hand, and the entries of the discharging paths 12 a and 12 b isshorter than that shown in FIG. 9. As a result, the wet treatment liquidintroduced through the introducing paths 10 a and 10 b is moreefficiently discharged to the discharging paths 12 a and 12 b.

While a structure in which the discharging paths are arranged betweenthe introducing paths in FIG. 16, the charging paths may in contrast bearranged between the discharging paths.

FIG. 17 illustrates a sixth embodiment of the wet treatment liquid feednozzle of the invention. The reference numeral 16 is an ultrasonicelement provided in the introducing path arranged between thedischarging paths 12 a and 12 b so as to impart an ultrasonic wave tothe wet treatment liquid.

The wet treatment liquid feed nozzle of this embodiment is suitablyapplicable to wet treatment of the back of an object to be wet-treated 1mainly transferred horizontally.

In this embodiment, the introducing path 10 is provided at the center,and discharging paths 12 a and 12 b are provided on the both sides withthe introducing path 10 in between in parallel with the introducing path10. The exit of the introducing path 10 is slightly lower than theheight of the entry of the discharging paths 12 a and 12 b. Thedifference k in height should preferably be within a range of from 1 to2 mm.

The present invention will now be described below in detail by means ofexamples of substrate washing. It is needless to mention that theinvention is not limited to these examples.

EXAMPLE 1

A 500 mm×400 mm rectangular glass substrate was provided.

The substrate surface was stained by immersing the glass substrate intopure water containing Al₂O₃ particles. The number of particles on theentire surface of the substrate after staining was measured, giving aresult of 41,630 particles. Only particles having a size of at least 0.5μm were measured.

After the aforesaid staining, washing was carried out by the transversedisplacement method as shown in FIG. 11, by the use of the wet treatmentliquid feed nozzle shown in FIG. 1. In this example, however, the backof the substrate was not washed.

Conditions for the wet treatment liquid feed nozzle were as follows:

Conditions for wet treatment liquid feed nozzle:

Nozzle length: 500 mm

Angle θ₁ of introducing path: 45°

Angle θ₂ of discharging path: 45°

Distance from substrate: 1 mm

Opening section width: 10 mm

Washing conditions were as follows.

Washing conditions:

Washing liquid: Electrolytic cathode ion water (pH: 10)

Washing liquid consumption: 12 L/min

Ultrasonic frequency: 1 MHz

Ultrasonic power: 150 W

Substrate feed speed: 20 mm/sec

(Net washing time=Opening dia/feed speed=(4 mm)/(20 mm/sec)=20 sec

Number of washing runs: One

After washing, there were observed 150 particles.

Comparative Example 1

A 500 mm×400 mm rectangular glass substrate was prepared as in theExample.

The substrate surface was stained by immersing the glass substrate intopure water containing Al₂O₃ particles. The number of particles on theentire surface of the substrate after staining was measured, giving aresult of 41,000 particles. Only particles having a size of at least 0.5μm were measured.

After the aforesaid staining, washing was carried out by the transversedisplacement method as shown in FIG. 19B, by the use of the wettreatment liquid feed nozzle shown in FIG. 52A.

Conditions for the wet treatment liquid feed nozzle were as follows:

Conditions for wet treatment liquid feed nozzle:

Nozzle length: 500 mm

Opening section width: 2 mm

Washing conditions were as follows.

Washing conditions:

Washing liquid: Electrolytic cathode ion water (pH: 10)

Washing liquid consumption: 25 L/min

Ultrasonic frequency: 1 MHz

Ultrasonic power: 900 W

Washing time: 20 sec

Number of washing runs: One

After washing, there were observed 640 particles.

The results of the Comparative Example 1 and the Example 1 are shown inFIG. 18B. As is clear from comparison of the both, the Example 1 gave awashing liquid consumption a half that in the Comparative Example 1, andachieved a cleanliness about four times as high as that in the latter.The ultrasonic power was ⅙.

EXAMPLE 2

Spin washing was carried out in this Example.

A six-inch circular glass substrate was provided.

The substrate surface was stained by immersing the glass substrate intopure water containing Al₂O₃ particles. The number of particles on theentire surface of the substrate after staining was measured, giving aresult of 20,140 particles. Only particles having a size of at least 0.5μm were measured.

After the aforesaid staining, washing was carried out by the rotatingdisplacement method by the use of the wet treatment liquid feed nozzleshown in FIG. 1.

Conditions for the wet treatment liquid feed nozzle were as follows:

Conditions for wet treatment liquid feed nozzle:

Nozzle length: 152 mm

Angle θ₁ of introducing path: 30°

Angle θ₂ of discharging path: 30°

Distance between substrate and opening section: 1 mm

Opening section width: 10 mm

Washing conditions were as follows.

Washing conditions:

Washing liquid: Electrolytic ion water

Washing liquid consumption: 1 L/min

Ultrasonic frequency: 1 MHz

Ultrasonic power: 60 W

Washing time: 10 sec

Substrate revolutions: 300 rpm

After washing, there were observed 13 particles.

Comparative Example 2

A six-inch circular glass substrate was provided as in the Example 2.

The substrate surface was stained by immersing the glass substrate intopure water containing Al₂O₃ particles. The number of particles on theentire surface of the substrate after staining was measured, giving aresult of 19,930 particles. Only particles having a size of at least 0.5μm were measured.

After the aforesaid staining, spin washing was carried out by the use ofthe wet treatment liquid feed nozzle shown in FIG. 52A.

Conditions for the wet treatment liquid feed nozzle were as follows:

Conditions for wet treatment liquid feed nozzle:

Nozzle length: 152 mm

Opening section width: 2 mm

Washing conditions were as follows.

Washing conditions:

Washing liquid: Electrolytic cathode ion water

Washing liquid consumption: 10 L/min

Ultrasonic frequency: 1 MHz

Ultrasonic power: 300 W

Washing time: 10 sec

Substrate revolutions: 300 rpm

After washing, there were observed 32 particles.

The results of the Comparative Example 2 and the Example 2 are shown inFIG. 18A. As in clear from comparison of the Comparative Example 2 andthe Example 2, even in rotating washing, the Example 2 gave a washingliquid consumption of a tenth that in the Comparative Example 2, anultrasonic power of a fifth, and a cleanliness about three times ashigh.

In addition to the foregoing examples, an experiment was carried outwith various opening section 6 widths D and various gaps H between thesubstrate and the wet treatment liquid feed nozzle. So far as therelationship of [pressure of wet treatment liquid] Pw≧[atmosphericpressure] Pa was satisfied, a high cleanliness as in the Examples 1 and2 was achieved with a small consumption of the washing liquid.

A seventh embodiment of the wet treatment liquid feed nozzle of theinvention is illustrated in FIGS. 19 and 20.

FIG. 19 is a sectional side view; FIG. 20A is a bottom view; and FIG.20B is a plan view.

In FIG. 19, 102 is a wet treatment liquid feed nozzle.

The wet treatment liquid feed nozzle 102 comprises an introducing path110 having an introducing port 107 for introducing a wet treatmentliquid 105 at an end thereof, a discharging path 112 having adischarging port 115 for discharging the wet treatment liquid 105′ aftera wet treatment to outside the wet treatment system and an openingsection 106 opening to an object to be wet-treated (substrate) 101provided at a crossing section 114 formed by causing the introducingpath 110 and the discharging path 112 to cross at the other endsthereof.

The opening section 106 has a mesh shape as shown in FIG. 20A. In theembodiment shown in FIG. 20A, seven large circles 106 L are arrangedlongitudinally in two rows, and smaller circles 106M and further smallercircles 106S are provided to fill up gaps between large circles, thusachieving the largest possible total opening area.

Because the mesh size is up to a certain level, the wet treatmentliquid, coming into contact with the surface of the object to bewet-treated 101, can be prevented from dropping from the opening sectionunder the effect of surface tension even when the wet treatment liquidfeed nozzle is separated from the object to be wet-treated 101. As aresult, leakage from the crossing section 114 to outside never occurs.

So far as such an effect is available, the shape of mesh is not limitedto that shown in FIG. 20A. A shape, a size and a number mayappropriately be selected in response to the kind of the wet treatmentliquid.

The total opening area should preferable be as large as possible asshown in FIG. 20A because of the possibility to irradiate ultrasonicwave efficiently.

Meshes may be formed by piercing, for example, a metal sheet (such as anSUS316L stainless steel sheet) by punching. Etching technique is alsoapplicable.

In this embodiment, as is clear from FIG. 20, three introducing paths110 are provided.

Three discharging paths 112 are provided in parallel with theintroducing paths 110, respectively. By providing a plurality ofintroducing paths and discharging paths in the longitudinal direction ofthe wet treatment liquid feed nozzle 102 (up-down direction in FIG. 20),it is possible to achieve a uniform longitudinal washing efficiency.

The surface of the wet treatment liquid feed nozzle 102 in contact withthe liquid should preferably comprises stainless steel having a passivefilm with an outermost surface consisting of chromium oxide alone for afluororesin such as PFA or for some particular kinds of wet treatmentliquid, stainless steel provided with a mixed film of aluminum oxide andchromium oxide on the surface, or titanium having an electrolyticallypolished surface for ozone water, with a view to avoiding elution ofimpurities into the wet treatment liquid. A liquid-contact surfacecomprising quartz is preferable for any wet treatment liquid except forfluoric acid.

The angle θ₁ between the introducing path 110 and the substrate 101 canappropriately be selected within a range of from 0 to 90°.

On the other hand, the angle θ₂ between the discharging path 112 and thesubstrate 101 can appropriately be selected within a range of from 0 to90°.

The angle θ₁ between the introducing path 110 and the substrate 101 andthe angle θ₂ between the discharging path 112 and the substrate 101 is aarbitrarily set considering the contact efficiency of the wet treatmentliquid with the substrate, the discharge efficiency of the object to betreated, the shape of the crossing section, and the shape and area ofthe opening section.

The distance H2 between the portion of the ceiling 118 facing the objectto be wet-treated (substrate) forming the crossing section 114, which isthe closest to the object to be wet-treated (substrate) 101, on the onehand, and the portion of the opening section 106 the closest to theobject to be wet-treated (substrate) 101, on the other hand, shouldpreferably be within a range of from 1 to 50 mm, or more preferably,from 2 to 20 mm. With a distance H2 smaller than 1 mm, the wet treatmentliquid becomes difficult to flow, resulting in a lower contactefficiency of the wet treatment liquid with the substrate and a poorerdischarge efficiency of the treated object. With a distance H2 of overthis range, on the other hand, the wet treatment liquid in a largequantity would be present in the wet treatment liquid feed nozzle 102,resulting in a larger weight of the wet treatment liquid feed nozzle102, and in troubles in displacement of the wet treatment liquid feednozzle 102.

The distance H1 (between the object to be wet-treated 101 and theopening section 106) should preferably be within a range of from 0.1 to5 mm, or more preferably, from 1 to 2 mm.

Because the value of H1 may not always be constant under the effect ofvibration of the transfer machine or an uneven surface of the substrateitself, it is desirable to provide a sensor for measuring Hl, andfurther, means for bringing the wet treatment liquid feed nozzle 102apart from, or closer to, the object to be wet-treated 101 in responseto a signal from the sensor. At least two aforesaid length measuringunits at the top and the bottom in FIG. 20A with the wet treatmentliquid feed nozzle in between. This is to achieve a uniform distancebetween the object to be wet-treated 101 and the opening section 106 forthe entire wet treatment liquid feed nozzle, and to control the flow ofthe wet treatment liquid without fail. The length measuring accuracyshould preferably be under 0.1 mm. This is because the lower limit ofthe distance between the wet treatment liquid feed nozzle and the objectto be wet-treated should preferably be 0.1 mm in view of the currentpractice of treatment of a large-sized substrate, and this is tocertainly control this distance.

In FIG. 19, 119 is a contact preventing gas ejecting section. Thecontact preventing gas ejecting section is provided at least on any ofthe sides of the introducing path 10 and the discharging path so as toprevent the opening section 106 from coming into contact with the objectto be wet-treated when the object to be wet-treated 101 is lifted up tocope with an imbalance between the pressure of the wet treatment liquidin contact with the open air at the opening section and the atmosphericpressure. Preferable gases applicable in such a use include nitrogen gasand an inert gas, and air free from impurities (particularly organicmatters) is also applicable.

FIG. 21 illustrates an eighth embodiment of the wet treatment liquidfeed nozzle of the invention.

In FIG. 21, 102 is a wet treatment liquid feed nozzle. The wet treatmentliquid feed nozzle 102 has the following configuration.

The wet treatment liquid feed nozzle 102 comprises an introducing path110 having an introducing port 107 for introducing a wet treatmentliquid 105 at an end thereof, a discharging path 112 having adischarging port 115 for discharging the wet treatment liquid 105 aftera wet treatment to outside the set treatment system, a crossing section114 formed by causing the introducing path 110 and the discharging path112 to cross at the other ends thereof, and opening section 106 openingto an object to be wet-treated (substrate) at the crossing section 114,and an ultrasonic element 116 provided opposite to the object to bewet-treated so as to impart an ultrasonic wave during wet treatment ofthe object to be wet-treated.

In this embodiment, a contact preventing N₂ nozzle 119 is provided as inthe foregoing tenth embodiment. This is not however always necessary.

FIG. 22B is a plan view, and FIG. 22A is a bottom view, respectively, ofthe wet treatment liquid feed nozzle shown in FIG. 21.

The ultrasonic element 116 gives an output of an ultrasonic wave havinga frequency of at least 19 KHz. It should preferable be a megasonicultrasonic element of a frequency within a range of from 0.2 to 5 MHz.

The angle θ₃ between the ultrasonic element 116 and the substrate 101can be appropriately selected within a range of from 0 to 90°, or morepreferably, from 2 to 45°.

Imparting such a megasonic ultrasonic wave gives a remarkable improvingeffect of cleanliness.

The case shown in FIG. 22 has a single ultrasonic element 116. As inFIG. 6, a plurality of ultrasonic elements may be provided. The caseshown in FIG. 6 comprises three ultrasonic elements 116 a, 116 b and116C in the longitudinal direction (up-down direction in the drawing).Provision of a plurality of ultrasonic elements permits change from timeto time of the ultrasonic frequency and output, thus leading to uniformwashing.

Apart from the longitudinal direction, a plurality of ultrasonicelements may be arranged in the transverse direction. They may also bearranged both in the longitudinal and transverse directions.

FIG. 23 illustrates a ninth embodiment of the wet treatment liquid feednozzle of the invention. In this embodiment, a plurality of steps 140 a,140 b, 140 c, 141 a, 141 b and 141 c are provided on the ceilingopposite to the treated surface of the object to be treated 101. Theultrasonic elements 116 a, 116 b and 116 c are provided on the ceilingsteps 140 a, 140 b, and 140 c sequentially from the left top to rightbottom in the drawing.

According to this embodiment, it is possible to impart an ultrasonicwave in counter current to the wet treatment liquid fed from theintroducing path 110 to the crossing section 114, since the ultrasonicelements 116 a, 116 b and 116 c are provided sequentially from the lefttop to the right bottom of the ceiling, and the steps of the ceilinggive substantially uniform gaps between the ultrasonic elements and theobject to be wet-treated, thus permitting uniform washing.

The ultrasonic elements 116 a, 116 b and 116 c may have differentfrequencies from each other.

In the embodiment shown in FIG. 23, rectifying sections 104 forachieving uniform flows of the wet treatment liquid are provided atportions of the introducing path 110 and the discharging path 112 facingthe crossing section 114. The rectifying section may be composed of, forexample, a filter or a slit.

The opening sections are of a mesh shape as in the foregoing seventhembodiment, as represented by 106 a, 106 b and 106 c.

FIG. 24 illustrates a tenth embodiment of the wet treatment liquid feednozzle of the invention.

In this embodiment, the discharging path 112 is provided at right anglesto the substrate 101, and introducing paths 110 a and 110 b aresymmetrically provided with the discharging path 112 in between.

In this embodiment, the wet treatment liquid is fed from the right andleft introducing paths 110 a and 110 b onto the opposite substrate 101.Leakage of the washing liquid is further reduced, and the washing liquidafter washing is more rapidly carried away into the discharging path112. Irradiation frequencies of the two ultrasonic elements 116 may bethe same or different. The two ultrasonic elements 116 may be oscillatedalternately at certain time intervals or simultaneously.

The opening sections are of a mesh shape as in the foregoing seventhembodiment, as represented by 106 a and 106 b.

FIG. 25 illustrates an eleventh embodiment of the wet treatment liquidfeed nozzle of the invention.

In this embodiment, the introducing path 110 is arranged at right anglesto the substrate 101, and the discharging paths 112 a and 112 b aresymmetrically provided with the introducing path 110 in between.

The opening sections are of a mesh shape as in the foregoing seventhembodiment, as represented by 106 a and 106 b.

FIG. 26 illustrates a twelfth embodiment of the wet treatment liquid ofthe invention.

This embodiment represents a case in which cilia 220 are provided on theperipheral edge of the opening section 106 for preventing leakage of theliquid.

The wet treatment liquid feed nozzle of this embodiment comprisesintroducing paths 110 a and 110 b each having an introducing port forintroducing a wet treatment liquid at an end thereof, a discharging path112 having a discharging port for discharging the wet treatment liquidafter a wet treatment to outside the set treatment system, a crossingsection 114 formed by causing the introducing paths and the dischargingpath to cross at the other ends thereof, an opening section 106 openingto an object to be wet-treated 101 at the crossing section 114, andcilia 220 provided on the peripheral edge of the opening section 106 inparallel with the normal of the treated surface of the object to bewet-treated 101.

Under the effect of the cilia 220, the wet treatment liquid in contactwith the treated surface of the object to be wet-treated 101 isdischarged from the discharging path 112 without leaking to outside thesystem.

The cilia 220 should preferably made of a water-repellent material witha view to further preventing liquid leakage. Preferable materialsinclude Teflon PFA{—(CF₂—CF₂)m—(CF₂—CFOR₂)n—}, PTFE{—(CF₂—CF₂)n—}, andnylon. The diameter of the cilia 220 should preferably be within a rangeof from 0.01 mm to 0.1 mm. With a diameter of over 0.1 mm, contact withthe object to be wet-treated 101 may cause a damage to the object to bewet-treated 101. A diameter of under 0.01 mm results in a lower strengthof the material itself. A length and a density of cilia may arbitrarilybe selected. The length should preferably be within a range of from 1 to2 mm.

The cilia 220 are provided on a nozzle having a structure as shown inFIG. 26 in this embodiment. It is however needless to mention that ciliamay be provided on any of the basic structures shown in the foregoingseventh to eleventh embodiments.

FIG. 27 illustrates the thirteenth embodiment of the wet treatmentliquid feed nozzle of the invention.

In this embodiment, a film 230 is used in place of the cilia presentedin the foregoing twelfth embodiment. All the other points are the sameas in the twelfth embodiment.

FIG. 28 illustrates a fourteenth embodiment of the wet treatment liquidfeed nozzle of the invention.

This embodiment is to prevent entanglement of air by providing anauxiliary path.

The wet treatment liquid feed nozzle of the fourteenth embodimentcomprises an introducing path 110 having an introducing port 107 forintroducing a wet treatment liquid at an end thereof, discharging paths112 a and 112 b having discharging ports 115 a and 115 b for dischargingthe wet treatment liquid after a wet treatment to outside the wettreatment system, a crossing section 114 formed by causing theintroducing path and the discharging paths to cross at the other endsthereof, an opening section 106 opening to an object to be wet-treated101 provided at the crossing section 114, and auxiliary paths 240 a and240 b communicating with the crossing section 114, provided at leastbetween the discharging paths 115 a and 115 b the object to bewet-treated 101.

When the balance between the pressure of the wet treatment liquid incontact with the object to be wet-treated 101 and the atmosphericpressure is disturbed by some vase or other, and the open air pressurebecomes higher, air flows into the crossing section and entangled intothe wet treatment liquid.

By providing a sensor 131 as shown in FIG. 38 described later, it ispossible to know the status of balance in pressure.

When there is a risk of breakage of pressure balance, the balance inpressure ca be maintained by ejecting the wet treatment liquid into thecrossing section.

FIG. 28 shows a case in which the auxiliary paths 240 a and 240 b areadded to the basic configuration comprising the two discharging paths112 a and 112 b with the introducing path 110 in between. It is howeverneedless to mention that the auxiliary paths may be added to a basicconfiguration having a single introducing path and a single dischargingpath, shown in FIG. 19.

FIG. 29 illustrates a fifteenth embodiment of the wet treatment liquidfeed nozzle of the invention.

FIG. 29A is sectional side view, and FIG. 29B is a plan view.

The wet treatment liquid feed nozzle of the fifteenth embodimentcomprises introducing paths 110 a and 110 b each having an introducingport for introducing a wet treatment liquid at an end thereof, adischarging path 112 having a discharging port 115 aa for dischargingthe wet treatment liquid after a wet treatment to outside the wettreatment system, a crossing section 114 formed by causing theintroducing paths 110 a and 110 b and the discharging path 112 to crossat the other ends thereof. An opening section 106 opening to an objectto be wet-treated provided at the crossing section, and a parallel flowsection 260 through which the wet treatment liquid flows in parallelwith the treated surface of the object to be wet-treated 101.

When the wet treatment liquid is introduced through the parallel flowsection 260, replacement of the wet treatment liquid after treatment andthe newly introduced wet treatment liquid is efficiently accomplished,so that the object to be wet-treated can always be wet-treated withfresh wet treatment liquid.

The length Lx the parallel flow section 260 should preferably be withina range of from 1 mm to 10 mm. With a length of under 1 mm, it isdifficult to control the flow direction. With a length of over 10 mm,the nozzle becomes excessively larger in size.

The wet treatment liquid flowing through the parallel flow section 260may come into contact with the object to be wet-treated 101, or may flowwithout coming into contact with the object to be wet-treated 101.

In the case shown in FIG. 29, the upper length Lx of the parallel flowsection 260 is substantially equal to the lower length Ly thereof. Whenthe lengths Ly=Lx for the parallel flow section 260, therefore, the wettreatment liquid does not come into contact with the object to bewet-treated in the parallel flow section, and is introduced into thecrossing section 114. In this case, the wet treatment liquid iscontrolled so as to be in parallel with the object to be wet-treated,enters the crossing section, comes into contact with the object to bewet-treated at the opening section and flows into the discharging path,thereby improving washing efficiency.

On the other hand, Ly=0 in the case shown in FIG. 30 giving a variant ofthe foregoing fifteenth embodiment. That is, the wet treatment liquidflows through the parallel flow section while being in contact with theobject to be wet-treated.

In this variant of the fifteenth embodiment, the mesh is a little deeperthan the opening section 106. In other words, a mesh plate 265 having amesh-shaped opening is provided near the beginning of the dischargingpath 112. By adopting this configuration, it is possible to avoidexhaustion of the treatment liquid upon closing a valve provided in thedischarging path from the proximity to the ultrasonic element 116 evenin stoppage of the wet treatment liquid.

The cross-sectional area of the discharging path 112 is larger on thecrossing section 114 side, and smaller on the discharge port 115 side.This is for arranging the ultrasonic element 116 at a position where anultrasonic wave can be efficiently imparted, and for discharging the wettreatment liquid after wet treatment promptly on the discharge port 115side.

FIG. 31 illustrates a sixteenth embodiment of the wet treatment liquidfeed nozzle of the invention.

The wet treatment liquid feed nozzle of the sixteenth embodimentcomprises introducing paths 110 a and 110 b having respectiveintroducing ports 107 a and 107 b for introducing a wet treatment liquidat ends on one side thereof, a discharging path 112 having a dischargingport 115 for discharging the wet treatment liquid after a wet treatmentto outside the wet treatment system, a crossing section 114 formed bycausing the introducing paths 110 a and 110 b and the discharging path112 to cross at the other ends thereof, an opening section 106 openingto an object to be wt-treated 101, and an inner extension 270 providedon the peripheral edge of the opening section 106, from the peripheraledge toward inside, of which the outer surface is in parallel with thetreated surface of the object to be wet-treated 101.

When such an inner extension 270 is provided, it is possible to preventair from the open air side from being entangled into the wet treatmentliquid, since the wet treatment liquid in contact with the object to bewet-treated 101 communicates with the open air only through a very smallgap between the object to be wet-treated 101 and the inner extension. Itis also possible to prevent leakage of the wet treatment liquid to theopen air side.

FIG. 32 illustrates a variant of the aforesaid sixteenth embodiment, inwhich the inner extension 270 comprises a material different from thematerial for the introducing paths 110 a and 110 b. Suitable materialsfor the introducing path include stainless steel such as SUS316L(particularly, stainless steel having an oxide passive film of chromiumoxide alone formed on the surface) and aluminum (aluminum having afluoride passive film formed on the inner surface). The inner extensionshould preferably be formed of a water repellent material such as PTFE,PVDF{(CFH—CH2)n—} or PFA.

FIG. 33 illustrates a seventeenth embodiment of the wet treatment liquidfeed nozzle of the invention.

The wet treatment liquid feed nozzle of the seventeenth embodimentcomprises introducing paths 110 a and 110 b having respectiveintroducing ports 107 a and 107 b for introducing a wet treatment liquidat ends on one side thereof, a discharging path 112 having a dischargingport 115 for discharging the wet treatment liquid after a wet treatmentto outside the wet treatment system, a crossing section 114 formed bycausing the introducing paths 110 a and 110 b and the discharging path112 to cross at the other ends thereof, an opening section 106 openingto an object to be wet-treated 101 provided at the crossing section 114,and a sealing member 280 provided on the peripheral edge of the openingsection 106 for sealing the crossing section 114 from outside whilebeing in contact with a support stand 281 of the object to bewet-treated 101.

An object of this embodiment is to cut off the wet treatment liquid fromoutside by completely sealing the crossing section 114 with a sealingmember 280, thereby discharging the wet treatment liquid after the wettreatment completely into the discharging path 112.

According to this embodiment, the sealing member permits achievement ofperfect prevention of liquid leakage.

Or, as shown in FIG. 33B, the sealing member should preferably be incontact with a portion allowing contact such as the outer periphery ofthe object to be wet-treated 101.

In this embodiment, it is not necessary to arrange the wet treatmentliquid feed nozzle movably in parallel with the object to be wet-treated101, but it suffices to provide the nozzle vertically or diagonallymovably relative to the object to be wet-treated 101.

FIG. 34 illustrates an eighteenth embodiment of the wet treatment liquidfeed nozzle of the invention.

The wet treatment liquid feed nozzle of the eighteenth embodimentcomprises an introducing path 110 having an introducing port 107 forintroducing a wet treatment liquid at an end thereof, discharging paths112 a and 112 b having respective discharging ports 115 a and 115 b fordischarging the wet treatment liquid after a wet treatment to outsidethe wet treatment system, a crossing section 114 formed by causing theintroducing path 110 and the discharging paths 112 a and 112 b to crossat the other end thereof, a opening section 106 opening to an object tobe wet-treated 101 at the crossing section 114, and an auxiliaryintroducing path 290 communicating with the discharging path 115 b. InFIG. 34, 270 is an inner extension provided on the peripheral edge ofthe opening section 106, from the peripheral edge toward inside, ofwhich the outer surface is in parallel with the treated surface of theobject to be wet-treated 101.

The wet treatment liquid is constantly fed from the introducing path 110to the crossing section 114. However, the crossing section 114 maysometimes become empty at the trailing or beading end of the object tobe wet-treated. A problem is that, upon introduction of the wettreatment liquid from the introducing path 110 when the next object tobe wet-treated arrives, and upon filling the entire crossing sectionwith the treatment liquid, the discharging path side contains air, andthe treatment liquid cannot be discharged by the use of a waterdischarge pump. Therefore, by feeding the wet treatment liquid from theauxiliary introducing path 290, it is possible to fill the dischargingpath 112 as well with the wet treatment liquid, thereby ensuring a statepermitting smooth flow of the treatment liquid. A reduced-pressure pumpcan eliminate the problem without the necessity of an auxiliaryintroducing path 290.

In this embodiment, a shutter 295 is provided for opening and closingthe opening section 106. When treatment of an object to be wet-treatedhas been completed and the process is in standby for the treatment ofthe next object to be wet-treated, continuing feeding the wet treatmentliquid with a valve V₂ kept open would lead to exhaustion of the wettreatment liquid. When introduction of the wet treatment liquid isdiscontinued by closing the valve V₂ air enters the entire wet treatmentliquid feed nozzle including the crossing section 114, and at the startof the next run of wet treatment, the wet treatment liquid entrappingthe air would be fed to the object to be wet-treated.

Air is prevented from entering the wet treatment liquid by filling theentire wet treatment liquid feed nozzle including the crossing section114 with the wet treatment liquid by closing the shutter 295, andclosing valves V₁, V₂ and V₃ in this state. When using the wet treatmentliquid feed nozzle for the next run, it suffices to open the shutter295, with the valves V₁, V₂ and V₃ opened, to feed the wet treatmentliquid to the object to be wet-treated.

FIG. 35 illustrates a variant of the foregoing sixteenth embodiment.

This variant of embodiment has the same basic structure as that shown inFIG. 24: discharging paths 112 a and 112 b are provided with two opposedintroducing paths 110 a and 110 b in between. The only difference ofthis case lies in that the distance between the exits of the introducingpaths 110 a and 110 b, on the one hand, and the entries of thedischarging paths 112 a and 112 b is shorter than that shown in FIG. 24.The wet treatment liquid introduced from the introducing paths 110 a and110 b is discharged more efficiently into the discharging paths 112 aand 112 b.

While the discharging paths are arranged with the introducing paths inbetween in FIG. 35, the introducing paths may be arranged with thedischarging paths in between.

In this variant of embodiment, liquid leakage is prevented by providinga film 230.

FIG. 36 illustrates a nineteenth embodiment of the wet treatment liquidfeed nozzle of the invention.

In this embodiment, the crossing section is divided by partitions 350 aand 350 b into three compartments 114 a, 114 b and 114 c.

By dividing the crossing section into a plurality of compartments, andfurther providing introducing paths 110 a, 110 b and 110 c anddischarging paths 112 a, 112 b and 112 c for the compartments 114 a, 114b and 114 c, respectively, and providing a valve (not shown), it ispossible to feed the wet treatment liquid only to limited portionsrequiring the wet treatment, thereby further reducing the consumption ofthe wet treatment liquid.

Independent ultrasonic elements 116 a, 116 b and 116 c may be providedin the compartments, respectively, and by appropriately selecting afrequency and a power for each compartment, it is possible to carry outa treatment suitable for each surface portion of the object to bewet-treated.

FIG. 37 illustrates first embodiment of the wet treatment liquid feednozzle apparatus of the invention.

The wet treatment liquid feed nozzle apparatus of this embodimentcomprises the wet treatment liquid feed nozzle of the invention providedwith a pressure controller 113.

The pressure controller 113 is provided at least on the discharging path112 side so as to take balance between the pressure of the wet treatmentliquid in contact with to open air at the opening section 106 (includingthe surface tension of the wet treatment liquid and the surface tensionof the treated surface of the object to be wet-treated) and theatmospheric pressure so that the wet treatment liquid in contact withthe object to be wet-treated 101 after a wet treatment flows into thedischarging path 112.

In this embodiment, the pressure controller 113 comprises areduced-pressure pump provided on the discharging port 115 side. Morespecifically, by controlling the sucking pressure of thereduced-pressure pump, the pressure controller 113 controls the pressureof the wet treatment liquid, and hence the difference between theatmospheric pressure and the pressure of the wet treatment liquid incontact with the object to be wet-treated 101. It is desirable to carryout control, taking account of the flow rate of the introduced wettreatment liquid and the flow rate of the discharged wet treatmentliquid which have an effect on the pressure of the wet treatment liquid.More particularly, it suffices to experimentally determine these valuesin advance by the use of an actual wet treatment liquid feed nozzle andan actual wet treatment liquid.

That is, a reduced-pressure pump is used for the pressure controller 113on the discharging path 112 side. Balance is taken between the pressureof the wet treatment liquid in contact with the open air at the openingsection 106 (including the surface tension of the wet treatment liquidand the surface tension of the treated surface of the object to bewet-treated) and the atmospheric pressure, by controlling the force ofthe crossing section 114 sucking the wet treatment liquid by means ofthe reduced-pressure pump. In other words, by assuming Pw≈Pa torepresent the relationship between the pressure Pw of the wet treatmentliquid in contact with the open air at the opening section 106(including the surface tension of the wet treatment liquid and thesurface tension of the treated surface of the object to be wet-treated)and the atmospheric pressure Pa, it is fed to the substrate 101 via theopening section 106, and the wet treatment liquid in contact with thesubstrate 101 almost never leaks to outside the wet treatment liquidfeed nozzle, and is discharged into the discharging path 112.

It is desirable to select a shape of the ceiling of the crossing section114, a shape of the boundary between the introducing path 110 and thecrossing section 114 and a shape of the boundary between the crossingsection 114 and the discharging path 112 such that a Coanda effect isavailable to facilitate taking balance of pressure.

By adopting the configuration as described above, it is possible toremove the wet treatment liquid 105 fed from the wet treatment liquidfeed nozzle to the object to be wet-treated (substrate) 101, withoutcoming into contact with portions other than the potion to which the wettreatment liquid has been fed (opening section 106), from the object tobe set-treated (substrate) 101.

FIG. 38 illustrates a second embodiment of the wet treatment liquid feednozzle apparatus of the invention.

In this embodiment, means for controlling the difference between thepressure of the wet treatment liquid and the atmospheric pressurecomprises a reduced-pressure pump (water discharge pump in thisembodiment) 117 provided in the downstream of the discharging path 112,a feed pump 133 provided in the upstream of the introducing path 110, apressure sensor 131 for detecting the pressure of the wet treatmentliquid in contact with the object to be wet-treated 101, and acontroller 132 for controlling driving of the reduced-pressure pump 117and the feed pump 133 by a signal from the pressure sensor 131.

While the embodiment shown in FIG. 37 is effective when the pressure ofthe wet treatment liquid on the introducing port 107 side is constant,in this embodiment, a more accurate pressure control is achieved and anexcellent cleanliness is available because the pressure of the wettreatment liquid is detected on the introducing side as well.

Now, another embodiment of the wet treatment apparatus of the inventionwill be described.

When composing a wet treatment apparatus by the use of the wet treatmentliquid feed nozzle 102 shown in FIGS. 19 and 20, the opening section 106of the wet treatment liquid feed nozzle 102 is directed toward thesubstrate 101 as shown in FIG. 11, and means for relatively moving thewet treatment liquid feed nozzle 102 and the substrate 101, such as aroller conveyor (not shown) of the substrate 101 should preferably beprovided.

The apparatus has a wet treatment liquid source and means for feedingthe wet treatment liquid from the wet treatment liquid source to theintroducing port of the wet treatment liquid feed nozzle. For casesrequiring treatment of the object to be wet-treated at a temperature of70 to 80° C. such as in a stripping process of resist, it is desirableto provide a heating unit, a temperature adjusting unit and atemperature holding unit at appropriate positions.

In FIG. 11, wet treatment liquid feed nozzles 102 aF and 102 aB make apair with the object to be wet-treated 101 in between to simultaneouslywet-treat the surface and the back of the object to be wet-treated.

In addition, three rows comprising wet treatment liquid feed nozzles(102 aF and 102 aB) for electrolytic ion washing (and embodiment of wettreatment), wet treatment liquid feed nozzles (102 bF and 102 bB) forextra-pure water rinsing (wet treatment), and, for example, wettreatment liquid feed nozzles (102 cF and 102 cB) for IPA (isopropylalcohol) drying are arranged sequentially in the travelling direction ofthe object to be wet-treated 101. Illustration of the opening section,details of the surrounding portions thereof and the pressure controllerare omitted here.

The both ends of the pair of wet treatment liquid feed nozzles 102 aFand 102 aB are brought into contact with each other to form atunnel-shaped space, through which the object to be wet-treated 101travels. Even when the wet treatment liquid flows from the end face side(a plane perpendicular to the sheet in the drawing) of the object to bewet-treated 101, therefore, the flowing wet treatment liquid can bereceived in the lower wet treatment liquid feed nozzle 102 aB.

Because the washing efficiency is high on the back (lower surface),ultrasonic elements (16 a and 16 b) are provided only on the surface(upper surface). When a single kind of wet treatment liquid is used forall cases, pressure control may be conducted with a single pressurecontroller.

FIG. 12 illustrates an embodiment in which the object to be wet-treatedis move up and down: FIG. 12A is a sectional side view, and FIG. 12B isa plan view.

FIGS. 13A, 13B and 13C are sectional view as viewed from above, in whichthe object to be wet-treated 101 is place upright. The wed treatmentliquid feed nozzle 102 is arranged in the longitudinal direction atright angles to the travelling direction of the object to be wet-treated101 in the longitudinal direction of the wet treatment liquid feednozzle 102, and the object to be wet-treated 101 is horizontallytransferred. In this case the object to be wet-treated has no up-downrelationship. Since the washing efficiency is the same for both thesurface and the back, the ultrasonic element 16 may be provided on theback (FIG. 13C), on the surface (FIG. 13B), or on the back and thesurface (FIG. 13A).

FIG. 14 is sectional side view, in which the object to be wet-treated isplace upright, and vertically transferred upward.

As in the case shown in FIG. 13, in the embodiment shown in FIG. 14, theobject to be wet-treated has no up-down relationship and the washingefficiency is the same for both the surface and the back. The ultrasonicelement 16 may therefore be provided on the back (FIG. 14C), on thesurface (FIG. 14B) or on the back and the surface (FIG. 14A).

FIG. 15 is a sectional side view as viewed from a side: the back is thelower surface and the surface is the upper surface. FIG. 15 represents acase where the object to be wet-treated 101 is horizontally placed andtransferred in the horizontal direction. As to the ultrasonic element16, FIG. 15B is generally employed since washing of the back can beaccomplished at a high washing efficiency.

For the washing step, the wet treatment liquid may be extra-pure water,electrolytic ion water, ozone water, hydrogen water or other washingliquid, and for the other wet treatment steps, an etching solution, adeveloping solution or a stripping liquid is suitably applicable.

EXAMPLE 3

A 500 mm×400 mm rectangular glass substrate was provided.

The substrate surface was stained b immersing the glass substrate intopure water containing Al₂O₃ particles. The number of particles on theentire surface of the substrate after staining was measured, giving aresult of 41,500 particles. Only particles having a size of at least 0.5μm were measured.

After the aforesaid staining, washing was carried out by the transversedisplacement method as shown in FIG. 11, by the use of the wet treatmentliquid feed nozzle shown in FIG. 19, 20A and 20B. In this example, theback of the substrate was not washed.

Conditions for the wet treatment liquid feed nozzle were as follows:

Conditions for wet treatment liquid feed nozzle:

Nozzle length: 500 mm

Angle θ₁ of introducing path: 45°

Angle θ₂ of discharging path: 45°

Distance from substrate: 1 mm

Opening section: Diameter 106L in FIG. 20A: 8 mm Diameter 106M in FIG.20A: 4 mm Diameter 106S in FIG. 20A: 2 mm

Washing conditions were as follows:

Washing conditions:

Washing liquid: Electrolytic cathode ion water (pH: 10)

Washing liquid consumption: 2.5 L/min

Ultrasonic frequency: 1 MHz

Ultrasonic power: 150 W

Substrate feed speed: 20 mm/sec

Net washing Time=Opening dia/feed speed =(4 mm)/(20 mm/sec) =20 sec

Number of washing runs: One

After washing, there were observed 156 particles.

Comparative Example 3

A 500 mm×400 mm rectangular glass substrate was prepared as in theExample 3.

The substrate surface was stained by immersing the glass substrate intopure water containing Al₂O₃ particles. The number of particles on theentire surface of the substrate after staining was measured, giving aresult of 41,000 particles. Only particles having a size of at least 0.5μm were measured.

After the aforesaid staining, washing was carried out by the transversedisplacement method as shown in FIG. 52B, by the use of the wettreatment liquid feed nozzle shown in FIG. 52A.

Conditions for the wet treatment liquid feed nozzle were as follows:

Conditions for wet treatment liquid feed nozzle:

Nozzle length: 500 mm

Opening section width: 2 mm

Washing conditions were as follows:

Washing conditions:

Washing liquid: Electrolytic cathode ion water (pH: 10)

Washing liquid consumption: 25 L/min

Ultrasonic frequency: 1 MHz

Ultrasonic power: 900 W

Washing time: 20 sec

Number of washing runs: One

After washing, there were observed 640 particles.

The results of the Comparative Example 3 and Example 3 are shown in FIG.39B. As in clear from comparison of the both, the Example 3 gave awashing liquid consumption of a tenth that in the conventional art, andachieved a cleanliness about four times as high. The ultrasonic powerwas ⅙.

EXAMPLE 4

Spin washing was carried out in this Example.

A six-inch circular glass substrate was provided.

The substrate surface was stained by immersing the glass substrate intopure water containing Al₂O₃ particles. The number of particles on theentire surface of the substrate after staining was measured, giving aresult of 20,000 particles. Only particles having a size of at least 0.5μm were measured.

After the aforesaid staining, washing was carried out by the rotatingdisplacement method by the use of the wet treatment liquid feed nozzleshown in FIG. 19.

Conditions for the wet treatment liquid feed nozzle were as follows:

Conditions for wet treatment liquid feed nozzle:

Nozzle length: 152 mm

Angle θ₁ of introducing path: 30°

Angle θ₂ of discharging path: 30°

Distance between substrate and opening section: 1 mm

Opening section width: 20 mm

Diameter 106L in FIG. 20A: 8 mm

Diameter 106M in FIG. 20A: 4 mm

Diameter 106S in FIG. 20A: 2 mm

Washing conditions were as follows:

Washing conditions:

Washing liquid: Electrolytic ion water

Washing liquid consumption: 1 L/min

Ultrasonic frequency: 1 MHz

Ultrasonic power: 60 W

Washing time: 10 sec

Revolutions: 300 rpm

After washing, there were observed five particles.

Comparative Example 4

A six-inch circular glass substrate was provided as in the Example 4.

The substrate surface was stained by immersing the glass substrate intopure water containing Al₂O₃ particles. The number of particles on theentire surface of the substrate after staining was measured, giving aresult of 19,930 particles. Only particles having a size of at least 0.5μm were measured.

After the aforesaid staining, spin washing was carried out by the use ofthe wet treatment liquid feed nozzle shown in FIG. 52A.

Conditions for the wet treatment liquid feed nozzle were as follows:

Conditions for wet treatment liquid feed nozzle:

Nozzle length: 152 mm

Opening section: 2 mm

Washing conditions were as follows:

Washing conditions:

Washing liquid: Electrolytic cathode ion water

Washing liquid consumption: 10 L/min

Ultrasonic frequency: 1 MHz

Ultrasonic power: 300 W

Washing time: 10 sec

Revolutions: 300 rpm

After washing, there were observed 32 particles.

The results of the Comparative Example 4 and the Example 4 are shown inFIG. 39A. As in clear comparison of the Comparative Example 4 and theExample 4, even in rotating washing, the Example 4 gave a washing liquidconsumption of a tenth that in the conventional art, an ultrasonic powerof a fifth, and a cleanliness about six times as high.

Now, a first embodiment of the fluid treatment apparatus of theinvention is illustrated in FIGS. 40 and 41.

FIG. 40 is a sectional side view of the fluid treatment apparatus. FIG.41(A) is a bottom view, and FIG. 41B is a plan view.

In FIG. 40, 302 is the fluid treatment apparatus. The fluid treatmentapparatus 302 comprises a fluid feed nozzle body 350 and lightirradiating means 380.

The nozzle body 350 has a fluid treatment path 314 which brings atreatment fluid from an opening 306 into contact with an object to betreated 301 and then brings the treatment fluid back to the opening 306,an introducing path 310 which introduces the treatment fluid into thefluid treatment path 314, and a discharging path 312 which dischargesthe treatment fluid brought from the fluid treatment path 314 back tothe opening 306.

Outside the nozzle body 350, there is provided light irradiating means380 for irradiating a light onto the object to be treated.

The used treatment fluid 305′ fed from the fluid treatment apparatus 302to the object to be treated (substrate) 301 is removed from the objectto be treated (substrate) 301 without coming into contact with portionsother than the portion (opening 306) to which the treatment fluid hasbeen fed. It is therefore possible to irradiate the light onto thetreatment fluid free from impurities, thus improving the irradiationefficiency.

The shape of the ceiling 318 near the opening of the nozzle body 350should preferably be a shape giving a Coanda effect which enables toeasily take balance in pressure and permits easy removal of bubbleshaving entered into, or produced in, the fluid treatment path 314.

As is known from FIG. 41, three parallel introducing paths 310 areprovided in this embodiment.

Three parallel discharging paths 312 are provided, respectively, tocorrespond to the three introducing paths 310. It is thus possible toachieve a uniform washing efficiency in the longitudinal direction byproviding a plurality of introducing and discharging paths in thelongitudinal direction (up-down direction In FIG. 41) of the fluidtreatment apparatus 302.

The nozzle body 350 is made of a material permitting light transmission.

The angle θ₁ between the introducing path 310 and the substrate 301 canbe appropriately selected within a range of from 0 to 90°.

The angle θ₂ between the discharging path 312 and the substrate 301 canbe appropriately selected within a range of from 0 to 90°.

The angle θ₁ between the introducing path 310 and the substrate 301 andthe angle θ₂ between the discharging path 312 and the substrate 301 arearbitrarily set in view of the contact efficiency of the treatment fluidwith the substrate, the discharge efficiency of the treated object, theshape of the fluid treating path, the shape of the opening, and the areathereof.

The distance H2 between the portion of the ceiling the closest to theobject to be treated (substrate) 301, facing the object to be treated(substrate), forming the fluid treating path 314, on the one hand, andthe portion of the opening 306 the closest to the object to be treated(substrate), on the other hand, should preferably be within a range offrom 1 to 50 mm, or more preferably, from 2 to 20 mm. A distance H2 ofunder 1 mm makes it difficult for the treatment fluid to flow, leadingto a lower contact efficiency of the treatment liquid with the substrateand a lower discharge efficiency of the treated object. A distance H2 ofover this range results, on the other hand, in the presence of muchtreatment fluid in the fluid treatment apparatus 302, leading to alarger weight of the fluid treatment apparatus 302, and troubles occurin displacement of the fluid treatment apparatus 302.

H1 (distance between the object to be treated 301 and the opening)should preferably be within a range of from 0.1 to 5 mm, or morepreferably, from 1 to 2 mm.

The value of H1 may sometimes vary because of vibration of the transfermachine or an uneven surface of the substrate. It is therefore desirableto provide a sensor for measuring H1 and means for separating orbringing closer the fluid treatment apparatus 302 from or to the objectto be treated in response to a signal from the sensor. At least two suchlength measuring units should preferably be provided at two positionswith the nozzle body 350 in between in FIG. 41A. This is with a view toensuring accurate control of the flow of the treatment fluid whilekeeping a constant distance between the object to be treated 301 and theopening 306 for the entire fluid treatment apparatus. The lengthmeasuring accuracy should preferably be smaller than 0.1 mm. Because thelower limit of the distance between the fluid treatment apparatus andthe object to be treated should preferably be 0.1 mm, and this distanceshould accurately be controlled.

In FIG. 40, 319 is a contact preventing gas ejecting section. Thecontact preventing gas ejecting section is provided at least in any ofthe introducing path 310 and the discharging path so that the openingsection 306 does not come into contact with the object to be treated 301upon lifting up the object to be treated 301, because of unbalancebetween the pressure Pw of the treatment fluid in contact with the openair at the opening 306 and the atmospheric pressure PA. The gas used forthis purpose should preferably be nitrogen gas or an inert gas, or maybe air free from impurities (particularly water).

A second embodiment of the fluid treatment apparatus of the invention isillustrated in FIG. 42.

In FIG. 42, 302 is the fluid treatment apparatus. The fluid treatmentapparatus 302 comprises a nozzle body 350 having light irradiating means380 and a pressure controlling means 313.

The nozzle body 350 has a fluid treating path 314 which, after bringingthe treatment fluid from the opening 306 into contact with the object tobe treated 301, brings the treatment fluid back to the opening 306, anintroducing path 310 for introducing the treatment fluid to the fluidtreating path 314, a discharging path 312 for discharging the treatmentfluid brought back to the opening 306 from the fluid treating path 314,and light irradiating means 380 for irradiating a light onto thetreatment fluid.

In this embodiment the pressure control means 313 is provided on thedischarging path 312 side so as to take balance between the pressure ofthe treatment fluid in contact with the open air at opening 306(including the surface tension of the treatment fluid and the surfacetension of the treated surface of the object to be treated) and theatmospheric pressure to ensure flow of the treatment fluid having beenin contact with the object to be treated 301 into the discharging path312 after the fluid treatment.

In this embodiment, the pressure control means 313 comprises areduced-pressure pump 317 provided on the discharging port 315 side.That is, the pressure of the treatment fluid, and hence, the pressuredifference between the atmospheric pressure and the pressure of thetreatment fluid in contact with the object to be treated 301, bycontrolling the sucking pressure of the reduced-pressure pump 317.

More specifically, by the used of the reduced-pressure pump 317 in thepressure control means 313 on the discharging path 312 side, the forceof the fluid treating path 314 to suck the treatment fluid in controlledby the reduced-pressure pump 317, thereby taking balance between thepressure of the treatment fluid in contact with the open air at theopening 306 (including the surface tension of the treatment fluid andthe surface tension of the treated surface of the object to be treated)and the atmospheric pressure. That is, by assuming that the relationshipbetween the pressure Pw of the treatment fluid in contact with the openair at the opening 306 (including the surface tension of the treatmentfluid and the surface tension of the treated surface of the object to betreated) and the atmospheric pressure Pa is Pw≈Pa the treatment fluidfed to the substrate 301 via the opening 306 and in contact with thesubstrate 301 is discharged into the discharging path 312 withoutlacking to outside the fluid treatment apparatus 302.

In this embodiment also, the ceiling of the fluid treating path 314should preferably have a shape producing Coanda effect, which makes iteasier to take balance in pressure, and permits easy removal of bubblesentering the fluid treating path 314 or produced bubbles.

The other points are the same as in the foregoing first embodiment.

Now, a third embodiment of the fluid treatment apparatus of theinvention will be described below with reference to FIG. 3.

This embodiment permits control, with a simpler system, the balancebetween the pressure of the treatment fluid in contact with the objectto be treated 301 and the atmospheric pressure by the use of lightirradiating means 380. This is effective particularly in the case wherethe treatment fluid is a liquid.

The pressure control means on the discharging path 312 side controls thebalance between the pressure of the treatment fluid in contract with theopen air at the opening 306 (including the surface tension of thetreatment fluid and the surface tension of the treated surface of theobject to be treated) and the atmospheric pressure by controlling, bymeans of the difference in height, the force of the fluid treating path314 to suck the treatment fluid brought about by the weight of thetreatment fluid itself based on the syphon principle produced by thedifference in height between the opening 306 and the discharging path312 end (end open to the open air).

More specifically, a water discharging unit 327 is connected to thedischarging port 315 of the nozzle body 350 via a water discharge piping325, and the water discharging unit 327 is held by a holder 328. Theholder 328 is attached to, for example a strut slidably vertically inthe drawing.

A valve 330 is attached to the leading end of the water discharging unit327. The valve 330 is opened and closed by a valve drive 329.

On the other hand, this embodiment has a controller 322 which drives arobot and the calve drive 329 on the basis of a signal from the pressuresensor 324 for detecting the pressure of the treatment fluid in theintroducing path 310. The robot is for moving up and down the holder328. When the valve 330 is open, the pressure of the treatment fluid incontact with the object to be treated can be controlled through verticaldisplacement of the water discharging unit 327.

A fourth embodiment of the fluid treatment apparatus of the invention isillustrated in FIG. 43. The same components in FIG. 43 as those in FIG.40 are assigned the same reference numerals, and description thereof isomitted here.

More particularly, the fluid treatment apparatus is provided with anozzle body 350, light irradiating means 380 and a attachment guide 385for detachably attaching the light irradiating means 380.

The light irradiating means 380 can be attached or detached by causingthe same along the attachment guide 385 vertically in the drawing.

When carrying out chemicals washing after detaching the lightirradiating means 380, for example, an ultrasonic element 316 can beattached to the same position by detaching the light irradiating means.

When attaching the ultrasonic element 316, it should preferably be anultrasonic element giving an output of an ultrasonic wave of a frequencyof at least 19 kHz, or more preferably, a megasonic ultrasonic elementof a frequency within a range of from 0.2 to 5 MHz.

The angle θ₃ between the ultrasonic element 316 and the substrate 301can be appropriately selected within a range of from 0 to 90°, orpreferably, from 2 to 45°.

Use of a megasonic ultrasonic element gives a remarkable improvingeffect of cleanliness.

FIG. 43 illustrates a case where single light irradiating means 380 or asingle ultrasonic element 316 is provided. FIG. 44 shows a case where aplurality of light irradiating means 380 or ultrasonic elements 316 areprovided. In the example shown in FIG. 44, three light irradiating means380 a, 380 b and 380 c are arranged longitudinally (in the up-downdirection in FIG. 44). Provision of a plurality of light irradiatingmeans as described above permits uniform washing because the lightwavelength or the output can appropriately be changed. Similarly, threeultrasonic elements 316 a, 316 b and 316 c may also be arrangedlongitudinally.

A plurality of light irradiating means 380 or ultrasonic elements may bearranged either longitudinally or in the transverse direction. They mayalso be arranged both in the longitudinal direction and in thetransverse direction.

Single light irradiating means 380 and a plurality of ultrasonicelements 316 may be mixed and may be simultaneously attached.

Now, a fifth embodiment of the fluid treatment apparatus of theinvention will be described below with reference to FIG. 45. The fifthembodiment has the same configuration as in the foregoing case shown inFIG. 38, and by using light irradiating means 380 in place of theultrasonic element 316, there are simultaneously available the advantagepresented in the twenty-fifth embodiment in addition to the advantagebrought about by light irradiation.

In this embodiment, means for controlling the difference between thepressure of the treatment fluid and the atmospheric pressure comprises areduced-pressure pump (a water discharge pump in this example) 317provided in the downstream of the discharging path 312, and a feed pump333 provided in the upstream of the introducing path 310. It may furthercomprise a pressure sensor 331 for detecting the pressure of thetreatment fluid in contact with the object to be treated 1, and acontroller 332 for controlling drive of the reduced-pressure pump 317and the feed pump 317 in accordance with a signal from the pressuresensor 331.

While the embodiment shown in FIG. 42 is effective when the pressure ofthe treatment fluid is constant on the introducing port 307 side, thepresent embodiment, in which the pressure of the treatment fluid on theintroducing side is detected, permits achievement of accurate pressurecontrol, giving an excellent cleanliness.

Now, a sixth embodiment of the fluid treatment apparatus of theinvention will be described below with reference to FIG. 8. The sixthembodiment has the same configuration as in the foregoing case shown inFIG. 8. Advantages of light irradiation are available by using lightirradiating means 380 a, 380 b and 380 c in place of the ultrasonicelements 16 a, 16 b and 16 c. In FIG. 8 the light irradiating means 380a, 380 b and 380 c are provided on the stepped ceiling portions 40 a, 40b and 40 c, respectively, including toward the right down, facing thetreated surface of the object to be treated 301.

Since, in this embodiment, light irradiating means 380 a, 380 b and 380c are provided on the right down portions of the ceiling in the sameapparatus, the gaps from the object to be treated are substantiallyuniform, thereby permitting uniform irradiation.

The light irradiating means 380 a, 380 b and 380 c may be composed oflight different in output and wavelength.

It suffices to provide at least one light irradiating means, togetherwith ultrasonic elements.

Now, a seventh embodiment of the fluid treatment apparatus of theinvention will be described below with reference to FIG. 9. Thisembodiment has the same configuration as the foregoing embodiment shownin FIG. 9 except that light irradiating means 380 is employed in placeof the ultrasonic element 16.

In the fluid treatment apparatus of this embodiment, the output and thewavelength of the light irradiated from the two light irradiating means380 may be the same or different. The two light irradiating means mayirradiate the light either in pulsation alternately at certain timeintervals or simultaneously.

An eighth embodiment of the fluid treatment apparatus of the inventionwill be described below with reference to FIG. 10. This embodiment hasthe same configuration as in the embodiment shown in FIG. 10 except thatlight irradiating means 380 is used in place of the ultrasonic element16.

A ninth embodiment of the fluid treatment apparatus of the inventionwill be described below with reference to FIG. 16. This embodiment hasthe same configuration as in the embodiment shown in FIG. 16 except thatlight irradiating means 380 a and 380 b are used in place of theultrasonic elements 16 a and 16 b.

A tenth embodiment will be described with reference to FIG. 17. Thetenth embodiment has the same configuration as that of the foregoingembodiment shown in FIG. 17, except that light irradiating means 380 isused in place of the ultrasonic element 3.

Another embodiment of the invention will be described with reference toFIGS. 21 and 22. This embodiment has the same configuration as that ofthe foregoing embodiment shown in FIGS. 21 and 22, except that lightirradiating means 380 is employed in place of the ultrasonic element116. The present embodiment is suitably applicable when he treatmentfluid is a liquid.

An eleventh embodiment of the fluid treatment apparatus of the inventionwill be described with reference to FIG. 24. The eleventh embodiment hasthe same configuration as that of the foregoing embodiment shown in FIG.24, except that light irradiating means 380 is used in place of theultrasonic element 116.

The output and the wavelength of irradiation from the two lightirradiating means may be the same or different. The two irradiatingmeans may be operated for irradiation in pulsation alternately atcertain time intervals or simultaneously.

A twelfth embodiment of the fluid treatment apparatus of the inventionwill be described with reference to FIG. 25. The twelfth embodiment hasthe same configuration as that of the foregoing embodiment shown in FIG.25, except that light irradiating means is used in place of theultrasonic element 116.

The output and the wavelength of irradiation from the two lightirradiating means may be the same or different. The two irradiatingmeans may be operated for irradiation in pulsation alternately atcertain time intervals or simultaneously.

A thirteenth embodiment of the fluid treatment apparatus of theinvention will be described with reference to FIG. 28. The thirteenthembodiment has the same configuration as that of the foregoingembodiment shown in FIGS. 28A and 28B, except that light irradiatingmeans 380 is employed in place of the ultrasonic element 116, andentanglement of the air is prevented by providing an auxiliary path.

A fourteenth embodiment of the fluid treatment apparatus of theinvention will be described with reference to FIGS. 29A and 29B. Thefourteenth embodiment has the same configuration as that of theforegoing embodiment shown in FIGS. 29A and 29B, except that lightirradiating means 380 is employed in place of the ultrasonic element116.

A fifteenth embodiment of the fluid treatment apparatus of the inventionwill be described with reference to FIGS. 30A and 30B. The fifteenthembodiment has the same configuration as that of the foregoingembodiment shown in FIGS. 30A and 30B, except that light irradiatingmeans 380 is used in place of the ultrasonic element 116. In the presentembodiment, there stands a relationship Ly=0 as shown in the embodimentof FIG. 14, i.e., the treatment fluid flows in contact with the objectto be treated in the parallel flow section.

A sixteenth embodiment of the fluid treatment apparatus of the inventionwill be described with reference to FIG. 32. The sixteenth embodimenthas the same configuration as that of the foregoing embodiment shown inFIG. 32, except that light irradiating means 380 is used in place of theultrasonic element 116, and an inner extension 270 is made of a materialdifferent from that for introducing sections 110 a and 110 b.

A seventeenth embodiment of the fluid treatment apparatus of theinvention will be described with reference to FIG. 33A. The seventeenthembodiment has the same configuration as that of the foregoingembodiment shown in FIG. 33A, except that light irradiating means 380 isused in place of the ultrasonic element 116.

As in the variation shown in FIG. 33B, portions which may be broughtinto contact with the other components on the outer periphery of theobject to be treated 1 (for example, the portion on which nosemiconductor device is formed) should preferably be brought intocontact with a sealing member 280 of the fluid treatment apparatus. InFIG. 33B, the reference numeral 380 represents light irradiating means.

An eighteenth embodiment of the fluid treatment apparatus of theinvention will be described with reference to FIGS. 34A and 34B. Theeighteenth embodiment has the same configuration as that of theforegoing embodiment shown in FIGS. 34A and 34B, except that lightirradiating means 380 is employed in place of the ultrasonic element116.

An nineteenth embodiment of the fluid treatment apparatus of theinvention will be described with reference to FIG. 35. The nineteenthembodiment has the same configuration as that of the foregoingembodiment shown in FIG. 35, except that light irradiating means 380 aand 380 b are used in place of the ultrasonic elements 116 a and 116 b.

The present embodiment is quite similar to the twenty-second embodiment,except that light irradiating means 380 is used in place of theultrasonic elements 116 a and 116 b.

An twentieth embodiment of the fluid treatment apparatus of theinvention will be described with reference to FIGS. 36A and 36B. Thetwentieth embodiment has the same configuration as that of the foregoingembodiment shown in FIGS. 36A and 36B, except that light irradiatingmeans 380 a, 380 b and 380 c are employed in place of the ultrasonicelements 116 a, 116 b and 116 c.

FIG. 46 illustrates the twentieth embodiment of the fluid treatmentapparatus of the invention.

In FIG. 46,

Reference numeral 301 is an object to be treated;

Reference numeral 302 is a fluid treatment apparatus;

Reference numeral 304 is a treatment fluid before use;

Reference numeral 305 is a treatment fluid after use;

Reference numeral 306 is an opening;

Reference numeral 307 is an introducing port;

Reference numeral 310 is an introducing path;

Reference numeral 312 is a discharging path;

Reference numeral 314 is a fluid treatment path;

Reference numeral 315 is a discharging port;

Reference numeral 319 is a contact preventing gas ejecting section;

Reference numeral 316 is an ultrasonic element;

Reference numeral 380 is light irradiating means;

Reference numeral H1 is a distance between the opening and the treatedsurface of the object to be treated; Reference numeral H2 is a distancebetween the ceiling of the fluid treatment section and the opening;

Reference numeral Θ₃ is an angle between the introducing path and thetreated surface;

Reference numeral Θ₂ is an angle between the discharging path and thetreated surface;

Reference numeral Θ₃ is an angle between the ceiling of the fluidtreatment section and the treated surface;

Reference numeral PA is the atmospheric pressure; and

Reference numeral Pw is the pressure of the treatment fluid.

This is an embodiment in which light irradiating means 380 and anultrasonic element 316 are simultaneously provided. In the case shown inFIG. 46, the light irradiating means 380 and the ultrasonic element 316are provided adjacent to each other. However, when simultaneouslyproviding the light irradiating means 380 and the ultrasonic element316, the arrangement id not limited to that shown in FIG. 46, but asshown in FIG. 9A the light irradiating means 380 may be provided on oneside and the ultrasonic element 16 may be provided on the other side,with the discharging path 12 in between.

In FIG. 46, one of the two light irradiating means 380 presented in theforegoing twelfth, thirteenth, sixteenth, seventeenth, eighteenth andnineteenth embodiments of the fluid treatment apparatus of the inventionmay be replaced by an ultrasonic element.

It is needless to mention that any other arrangement may be adopted.

When generating a chemically active species by irradiating a light to afluid, for example, the light may fail to reach a large depth (theposition of the object to be treated 301 is the deepest in the casesshown in FIG. 46). As a result, the concentration distribution of theactive species may sometimes be the densest neat the light irradiatingmeans 380 and the thinnest on the surface of the object to be treated301 where it is desired to achieve the densest concentration.

Although the cause is not necessarily clear, the present invention foundthat imparting an ultrasonic wave together with irradiation of the lightmade it available the densest concentration near the surface of theobject to be treated.

It is therefore possible to increase the concentration of the activespecies on the surface of the object to be treated by providing thelight irradiating means 380 and the ultrasonic element 316, andsimultaneously operating the both.

FIG. 47 illustrates a twenty-first embodiment of the fluid treatmentapparatus of the invention.

The apparatus of this embodiment comprises a fluid treating path which,after bringing the treatment fluid from the opening 506 into contactwith the object to be treated 301, brings the treatment fluid back tothe opening 506, an introducing path 510 for introducing the treatmentfluid into the fluid treating path, a discharging path 512 fordischarging the treatment fluid brought from the fluid treating path 514back to the opening 506, and liquid sumps 520 a and 520 b providedaround the opening 506. The fluid treating path comprises a gas area GA,a liquid area LA, and a gas-liquid interface BA.

The liquid sumps are continuously formed around the opening 506, so thatthe liquid sump 520 a and the liquid sump 520 b in FIG. 47 communicatewith each other.

In this embodiment, the discharging path 512 is provided above theliquid sump 520 b. The treatment fluid after treatment is thereforedischarged only through the liquid sumps.

In this embodiment, the discharging path 512 communicates with theliquid sump 520 b through a fine groove 521 b. The treatment fluid aftertreatment collected in the liquid sumps sucked into the discharging paththrough the fine groove under the effect of capillary action withoutdropping and discharged.

A twenty-second embodiment of the fluid treatment apparatus of theinvention is illustrated in FIG. 48.

The fluid treatment apparatus of this embodiment comprises a fluidtreating path 514 which, after bringing the treatment fluid from theopening 506 into contact with the object to be treated 301, brings thetreatment fluid back to the opening 506, and introducing path 510 forintroducing the treatment fluid into the fluid treating path 514, adischarging path 512 for discharging the treatment fluid brought fromthe fluid treating path 514 back to the opening 506, a pressureadjusting port 530 for adjusting the position of the gas-liquidinterface communicating with the fluid treating path 514, and liquidsumps 520 a and 520 b provided around the opening 506. The fluidtreating path 514 and the discharging path 512 communicate with eachother through the liquid sump 520 b.

A treatment liquid serving as the treatment fluid is introduced from theintroducing path 510 into the fluid treating path 514 and is broughtinto contact with the object to be treated 301. By applying anappropriate pressure at the pressure adjusting port, when a gas ispresent in the treatment fluid, the gas is directed toward the pressureadjusting port and leaves the treatment liquid, thus forming a gas areaGA and a liquid area LA in the fluid treating path 514. BA is agas-liquid interface. The gas from the gas area GA is totally orpartially discharged through the pressure adjusting port 530 to outside.

In this embodiment, on the other hand, the treatment liquid is collectedin the liquid sumps 520 a and 520 b. The fluid treating path 514 and thedischarging path 512 do not communicate directly with each other, butcommunicate with each other through the liquid sump 520 b and a finegroove 521 b. The treatment liquid is therefore collected in the liquidsump 520 b, sucked up through the fine groove 521 b under the effect ofcapillary action, and discharged from the discharging path 512.

In this embodiment, an ultrasonic element 516 is provided for thepurpose of imparting an ultrasonic wave to the treatment liquid. When anultrasonic wave or a light is applied to the treatment liquid by meansof the ultrasonic element 516, and when the treatment liquid is awashing solution, for example, there is available a remarkableimprovement of washing effect. Light irradiating means 580 may beprovided at the same position in place of the ultrasonic element 516.

Since the fluid treating path 514 does not communicate directly with thefluid discharging path 512 in this embodiment, the space in the fluidtreating path 514 has a close tightness, thus facilitating pressurecontrol in the fluid treating path 514.

FIG. 49 illustrates a twenty-third embodiment of the fluid treatmentapparatus of the invention.

This embodiment comprises the embodiment shown in FIG. 48 furtherprovided with light irradiating means 581 arranged on the surface of theceiling 518 of the fluid treatment apparatus main body between theintroducing path 510 and the pressure adjusting port 530.

As described as to the foregoing embodiments, it is possible to conductsterilization and the like by irradiating a light of an appropriatewavelength to the treatment fluid by the use of the light irradiatingmeans 581. In the present embodiment, the light may be irradiated forthe purpose of decomposing the gas in the gas area GA.

The other points are the same as those in the embodiment described withreference to FIG. 48.

Now, embodiments of the washing system will be described.

A washing system is illustrated in FIG. 50.

The washing system of this embodiment is the same as that of the firstembodiment of the liquid treatment apparatus of the invention shown inFIG. 40, and comprises gas treatment units 302 aF and 302 aBcommunicating with washing units 302 bF and 302 bB.

More specifically, the washing system of the embodiment comprises a gastreating path 314 which, after bringing the treatment gas from anopening 306 shown in FIG. 40 into contact with the object to be treated301, brings the treatment gas back to the opening 306, an introducingpath 310 for introducing the treatment gas into the gas treating path314, a discharging path 312 for discharging the treatment gas broughtfrom the gas treating path 314 back to the opening 306, and gastreatment units 302 aF and 302 aB comprising light irradiating means 380for irradiating a light onto the treatment gas in the gas treating path314, which communicate with washing units 302 bF and 302 bB for washingthe object to be treated 301, having been treated by the gas treatmentunits 302 aF and 302 aB, with a washing liquid.

This embodiment will be described further in detail below.

When composing a washing system with the use of the gas treatment unit302 (302 aF and 302 aB in FIG. 50A) shown in FIG. 40, the openings 306of the gas treatment units 302 aF and 302 aB is directed toward theobject to be treated 301 as shown in FIG. 50A, and it suffices toprovide means for causing relative displacement of the gas treatmentunits 302 aF and 302 aB and the object to be treated 301 in the arrow Adirection, for example, a roller conveyor (not shown) of the substrate301.

The washing system has a treatment gas source (not shown) and means (notshown) for feeding the treatment gas from the treatment gas source tothe introducing ports 307 of the gas treatment units 302 aF and 302 aB.A heater, a temperature adjusting unit and a temperature holding unitshould preferably be provided at appropriate positions to cope with thenecessity to treat the object to be treated at a temperature of 70 to80° C. as in a stripping step of resist.

With a view to simultaneously conducting gas treatment of both thesurface and the back of the object to be treated 301, the gas treatmentunits 302 aF and 302 aB are arranged in pair with the object to betreated 301 in between in FIG. 50B.

As shown in FIG. 50B, the pair of gas treatment units 302 aF and 302 aBare in contact with each other at the both ends thereof to form atunnel-shaped space, through which the object to be treated 301 travels.Therefore, even when the treatment fluid flows from the end face (aplane perpendicular to the surface of the sheet in the drawing), theflowing treatment fluid can be received by the fluid treatment unit 302aB in the downstream thereof.

Washing units 302 bF and 302 bB are further provided in the downstreamin the travelling direction of the object to be treated 301.

The washing units 302 bF and 302 bB each comprises a washing treatmentpath which, after bringing the washing liquid from the opening intocontact with the object to be treated, brings the washing liquid back tothe opening, an introducing path for introducing the washing liquid intothe washing treatment path, another introducing path for introducing thewashing liquid brought from the washing treatment path back into theopening into the washing treatment path, and a discharging path fordischarging the washing liquid brought from the washing treatment pathback into the opening. The system is also provided with pressure controlmeans (not shown). More particularly, the system has the same basicstructure as that of the fluid treatment apparatus shown in FIG. 40,except however that the washing unit having an ultrasonic elementattached thereto in place of the washing unit except for lightirradiating means or the light irradiating means. Any other appropriatewashing unit may of course be used.

Further in the downstream of the washing units 302 bF and 302 bB, thereare provided extra-pure water rinsing units 302 cF and 302 cB forrinsing with extra-pure water, and IPA dryers 302 dF and 302 dB for IPA(isopropyl alcohol) drying. The extra-pure water rinsing units 302 cFand 302 cB and the IPA dryers 302 dF and 302 dB have the same structureas that of the washing units 302 bF and 302 bB. However, because thewashing efficiency is high for the back (lower surface), the ultrasonicelement is provided only for the surface (upper surface). When a singletreatment fluid is used for all the purposes of treatment, pressurecontrol may be accomplished with a single pressure controller.

The case where the object to be treated 301 travels horizontally isshown in FIG. 50A. FIG. 51 illustrates a case where the object to betreated 301 is moved in the vertical direction (up-down direction).Since, in this case, the surface and the back of the object to betreated have no up-down relationship, the surface and the back areuniformly washed.

What is claimed is:
 1. A wet treatment liquid feed apparatus forsubjecting an object to a wet treatment therein, the wet treatmentliquid feed apparatus comprising: a nozzle assembly including: anintroducing pipe having an introducing port to introduce the wettreatment liquid at an end thereof; a discharging pipe having adischarging port to discharge the wet treatment liquid to outside thedischarging pipe after the object has been subjected to the wettreatment; a crossing section formed by connecting another end of saidintroducing pipe and an end of said discharging pipe, respectively; andan opening section provided at a bottom of said crossing section andopen to the object to be subjected to the wet treatment; and a pressurecontroller to control a difference between a pressure of the wettreatment liquid in contact with the object to be wet-treated and anatmospheric pressure to prevent the wet treatment liquid in contact withthe object to subjected to the wet treatment via said opening sectionfrom flowing to outside said discharging pipe.
 2. A wet treatment liquidfeed apparatus according to claim 1, further comprising an ultrasonicmechanism to impart an ultrasonic wave to said wet treatment liquid. 3.A wet treatment liquid feed apparatus according to claim 1, wherein aportion of a ceiling opposite to the treatment surface of said object tobe wet-treated is formed into a waved shape having a plurality of steps,and a plurality of ultrasonic elements are provided at an angle to thetreatment surface of the object to be wet-treated on said steppedportion.
 4. A wet treatment liquid feed apparatus according to claim 1,wherein said discharging pipe is formed at a center of one side of saidcrossing section and two introducing pipes are formed around a center ofanother side of said crossing section.
 5. A wet treatment liquid feedapparatus according to claim 1, wherein said introducing pipe is formedat a center of one side of said crossing section and two dischargingpipes are formed around a center of another side of said crossingsection.
 6. A wet treatment liquid feed apparatus according to claim 1,wherein there is provided a measuring section capable of measuring thelength of the distance to the wet treatment surface of said object to bewet-treated.
 7. A wet treatment apparatus according to claim 1,comprising: a displacement mechanism to displace said wet treatmentliquid feed apparatus and said object to be subjected to wet treatmentrelative to each other; a wet treatment liquid feed source to supply thewet treatment liquid; and a feeding mechanism to feed said wet treatmentliquid from said wet treatment liquid feed source to the introducingport of said wet treatment liquid feed apparatus.
 8. A wet treatmentliquid feed apparatus of claim 1, wherein the crossing section issubstantially rectangularly parallelepiped.
 9. A wet treatment liquidfeed apparatus of claim 1, wherein the introducing pipe extends upwardsfrom a longitudinal side of the crossing section.
 10. A wet treatmentliquid feed apparatus of claim 1, wherein the discharging pipe extendsupwards from a longitudinal side of the crossing section.
 11. A wettreatment liquid feed apparatus of claim 1, wherein the crossing sectionis substantially rectangularly parallelepiped and the introducing pipeand discharging pipe extends upwards from opposing longitudinal sides ofthe crossing section.